Final Exam 2 (20%)

Question

A string p is a prefix of a string s if the leading characters of s are identical to p. For example, "abc" is a prefix of "abcde". Develop a function prefix that checks if a C string p is a prefix of another C string s.

p是s的前綴若s開頭的一段字串等於p。例如，"abc"是"abcde"的前綴。寫一個程式 判斷字串p是否字串s的前綴。

Example input 1:

abc
abcde

Example output 1:

abc is a prefix of abcde

 

Example input 2:

bc
abcde

Example output 2:

bc is not a prefix of abcde

 

Answer 1

Hidden content!
   **    *** ****  ***
  **** * *  ** *** **  *

int main()
{
  * **    *** char   ** ** *
   **    *****    int i,c=0;
**    *   * *  **       * * *  **   ***    * 
**  ****    * * * * ** *   ** **  ***** **** *  * 
  ****   **   ***    * *** *       ***** *
   * * ** ***  *** {
**** *   *  * ** ** * *   * *    * **
*       ***  * * **   *  *** {
 * **   **  ** ** *     *  * ** **     *** * * ** *** ***   * *   
*  **  ** * *  ** *  *   *  * *    * * ** **   *** *  * ****  {
   ****                    *** * **   *   c=0;
*  *   **  * **  *** * *** **** *  ****   ****  ****   }
*** *  ** ***** *      * *  * * *    *******  ****    else ****    ******** *         ***
  ** ** *   *     *  *  ****  *  *** *   ** ** * *  ***     * * {
 * *   **** *      **      * **    ** * *   ***   * *  *  ****  **  *  c++;
*** *  * *  **   ******* *  *** * *      *    * ****    * * *  }
**     **   * * * * *   * *** }
 *    **  ***  
*  ***      *   if(c==0)
* * ** *       *   ***   *  **      *** * is not a prefix of   *****  ** * 
  *  *** ** else
 **  **** *  ** **  ***    *    *** *  ****  * *  **** is a prefix of   **  **** **
 *  * ** * *   * }
**  **   * *   return 0;
}

Comments

prog.c: In function 'main':
prog.c:8:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&a);
           ^
prog.c:9:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&b);
           ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

prog.c: In function 'main':
prog.c:10:6: warning: implicit declaration of function 'stlen' [-Wimplicit-function-declaration]
   if(stlen(b)>strlen(a))
      ^~~~~
/tmp/ccnE3ufV.o: In function `main':
prog.c:(.text+0x5b): undefined reference to `stlen'
collect2: error: ld returned 1 exit status

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Correct output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 2

Hidden content!
** * ** * **  ** **
  **  *** *         * **  ** 
int main()
{
  ***** **** * *** ap;
***  * * ** *   *********  *   *    **   *  || ap=a)
  ***** *******  *  ** **** * **  is a prefix of abcde\n");
* ***       *    
 ***** *****
 * **   **  ** ****  *** *    ** ***    * ** is not a prefix of abcde");
 * ** * **   **     *   * * * * * * *** ** *** *  *  ** * ******  * **    * *  ** 0;
 **              * ** ***   *  * *  *   * **** **  *  **    *  *     
  

Comments

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

Answer 3

Hidden content!
*  *  *******  ** 
  *  *     **  *****  

char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
* *   *  ** * *      * * ***** * i<pl; i++)
* ** **  * ** ***  ** **  *
* *    ***  *    ** *******   **  * * * *** *** ****** ** (p[i]==s[i])
 *      *      *** *     * **** ***   **  * **  ** *   *
*   *  **  ** ** ***  * *        *  **  *  ***   ****  * * * **  * * * ** * *** *** *  * ***
* *** ** * * *  *** *   *********  ** * ********   *****    ***** *   *  ** * ****   *   **** ***  
******** *** *   **  *****  * ** *   ******** ** * *    *    * * * * *   ** * *** * *** *  *   *   **   * ***  * * 1;
*  * ** ***  * ***   *  ** * **   * *** *  ** * ** *    **  *   *** **** **   *
*** * *  *  *   * **  ** ***  **   ***    * ** *  **  *   
*    **   *   * *   **   ****  **  * ** * **** ** * ** **  if(p[i]!=s[i])
**     *** *   *   *  ** *** ** * *  *****   * *  * * 
**** * **  *   **** * *  *  ***  * *  * ***     **  *** ** **     *    ** 0;
**** *  *** ******* **  * *** *****  ** *  **  * *** ****
** * * ******* ******    * ** 
}


int main()
{
 **    *** ** * *  
 ******  *
    ****  **  ",p);
 *   ***   * **    * 
 * * *    *** * *  * 

sl=strlen(s);
pl=strlen(p);


**** ** *   * && pl<sl)
{

*  ********  *** *  ** **   * ***** is a prefix of %s",p,s);
}else
{
printf("%s is not a prefix of %s",p,s);
}





}

Comments

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 4

Hidden content!
#include<stdio.h>
#include<string.h>
int main()
{
  *  * **   * *   ********  *  a[99],b[99];
    int l,i;
***** **    * ** *    * ** *** **** ** ** ***
* **  ******    * ***  * **  *  **   *
 ***  ***   *    * ** * *   ****** ***
  *** * **   ** ** *  *  * **  *   *  
    {
*     ***** * **** * ** **** **  *** *   * **  *  ** * *   *  
     * * * * **  * * *** ****   * **** *  *    *    * 
 * ** **   *   *  * **  ****  ***        * *  ******  *** *  ** *** * *   **  *** ***** * *** a prefix of %s",a,b);
* ****  ** *  *** **  *    **  * ** *      * *   ***   *   ***    * * * ***    **  * *  
* * ***  ** * ****** * *    ***  * *  * * *  * *  *  *
* *** *  ** *      ***   **  *   **   ***  ** ** * * **   ** *
*  **       * *****         *   **  ** * *    * **
*    *   ** *  * * * **  ** * ******  *     ** **** * *   **  **   ** ***      **    ** *  not a prefix of %s",a,b);
** *  *  ***  **  *      *   ***     ****  * *  * *** * *  **    *  * **    ** ***** *
*** **    *****    *   ******   **  *** *  * * *  **** 
    }


}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 5

Hidden content!
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

int prefix(char a[100],char b[100]);


int prefix(char a[100],char b[100])
{
*** *******  **** * *  * * *  *  **    i;
* **** *  * *   ** * *** ** *    count=0;
*   ** *  ***  ** **** ****   len;

  *** ***  * *      * *  * **** ** 

*** ***********  ** ***   *      *** ***   *   *
* **   *** * *      *** **      *
    *    ** *  *  * ** ***     * *  **  ***  ******** **   ** *     *
 *    *  * * * *  *  *  *  ****** *** **  *  ***  *****     *  
* *  ** * * **  *    ******* ***  ** *  * * ***** *** * ***       *** **   *  **** 
*  *  ** ** *      **    *** **  * **** *  ****  *  *
**  ** ***  *   **** *      ** **  *


 *  * ***** * * ** * **** **** * * *** *
* **   * *  ** *     * * * *  *
 **   * ** ***  ***   * ***    * **   *  *** *     **   ** ***   * 1;
** *  **   ***   *** ***
    * *** *  *   ** *  ***   

   return 0;
}


int main()
{
 *** *** **  * *    ***  * **  a[100];
** *  * *    *  * * ***  b[100];


  ** *  *    *    **  * ** ***   *  **    ** * **  ** *   *   * *
    * ** ****      * ***  * ***** *   **  *  *** *    *

 ** *** *  **** *** *** **** * *** ** **   ** 
** * * ** ****   ***  *   *      ** *     **

 ***   *     ** *   * ******  * *  * ****

 {
* *  **  ***** **   **** *  *  **** **    *****  **  * *  * is a prefix of %s",a,b);
***     **   **   ** * *    *
 * **     *** **  * *  ******
  *   *    *** *  ****   **
  **  * * *****    * **  *  ***  *    **** * *   ** **  * *  *  ******* ** * **  *  * * is not a prefix of %s",a,b);
   *** ** **   *  * ** ** *


 *   *  * ** * ****  **** * *  * 0;
}

Comments

prog.c: In function 'main':
prog.c:45:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&a);
               ^
prog.c:45:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&a);
                    ^
prog.c:46:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&b);
               ^
prog.c:46:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&b);
                    ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 6

Hidden content!
 * ***  * *** **  * * **
* **   * *     * *    

int **  
{
  ***  ** * ***       * ** *******  ****** no idea, I *    even do it in the  *** ****** *  * 
 *    *****  * *** ** **   *** 0;
}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 7

Hidden content!
#include  *   *** *** * 
#include *  *   *   * ****
#include  *****  * *  ** 

int pref(char[],char[]);

int main(){

      *    ** *       *  * p[10],s[10];
*      * ** * ****       ** * num;

* ***  ** * * * **    *  **   ** *  
*      *  ** *  **  ** *  * ** ****
  ** * *     ** ** **  *  *  * * ** * ***** *** *
*    ** **** * **    *****       * *   * ******* *  * 

   *** * **** **  * * *** *   = pref(p,s);

* *  * *** * * *   * ***   * *
 ** **    * ** ***   ** ** **** * *** *   ***  *   **  *  ****  *       *     is a prefix of %s",p,s);
**   ****    **  *   *  **   **  ***   *
   **  *    *** **** ********      *   ***  *        **   ** **   * is not a prefix of %s",p,s);


 return 0;
}

int pref(char p[30],char s[30]){
     *  **    *  *   *********   i;

****  ***  ** ** *   **        *  *** * *  * **   * 
 *    *** *** ** *** * **     *   **  * * *****  **   ***  *   *  *   * **** ******  **** *****  * * * ** **
*   ** *       *   * *  * *   **   *  **  ** * * *    * ** **  *   * **** * ** *    **  *     ***** ***   ** is a prefix of %s",p,s);
* * *   *   *  *  *******  *  ***       ** ***  *  * * *  ** * 
*    ** ** * ***  ** *  * ***     **** ** * **   * * ** *   *  ***  * ** *   ** ***    ***   is not a prefix of %s",p,s);

 * * *  *    **** * ****** 

}

Comments

prog.c: In function 'main':
prog.c:12:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:13:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/tmp/cc0tBG5r.o: In function `main':
prog.c:(.text+0x1f): warning: the `gets' function is dangerous and should not be used.

---

prog.c: In function 'main':
prog.c:10:13: error: stray '#' in program
     int num;#include <stdio.h>
             ^
prog.c:10:14: error: 'include' undeclared (first use in this function)
     int num;#include <stdio.h>
              ^~~~~~~
prog.c:10:14: note: each undeclared identifier is reported only once for each function it appears in
prog.c:10:23: error: 'stdio' undeclared (first use in this function)
     int num;#include <stdio.h>
                       ^~~~~
prog.c:14:1: error: expected expression before 'int'
 int pref(char[],char[]);
 ^~~
prog.c: In function 'main':
prog.c:23:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:24:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^
prog.c: In function 'main':
prog.c:51:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:52:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~

---

prog.c: In function 'main':
prog.c:14:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:15:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^

Answer 8

Hidden content!
***    ** *   ** *** *
 *  *  * * ***** ***   **

int main()
{
****** * * length1, *      c;
    *****   * a[100];
**   * *   * b[100];
* ** *  * d[100];

**  * *** * *     *   ***   **** ***  
 * * **   * ****  **        * ** * *

* **** ** ****    **** *

 ***  *   * ***  *  *

*****   * * * ** * **
** ** *
*   ****   ***       * **     is a prefix of  ** **  *
***  **** 
 *   * *** **** 
 ****    *
**   * **  * ** **   is not a prefix of  ** *      ** 
** *  **

}

Comments

prog.c: In function 'main':
prog.c:11:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&a);
          ^
prog.c:12:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&b);
          ^
prog.c:24:11: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
           ^
prog.c:24:33: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
                                 ^

Answer 9

Hidden content!
 ** *** *  ** **   ***
       ** *  **    * * 

int main()
{
 **** ******** * ****  *  *  *   str;
   ** *  **  *   * *** * * i, p, s;

    *** * **  *   **   **  * **   * ** ***     &p, &s);

*     * ** **** **  * ***** *   (i<=0; &p; i++);
   * * ********* * * ***  *  ***  
    ** **    * *   *       * ** *****    * *  ** **  * * &p);
* ***** *  **  * *  *** *   ** *  **  *   **
   ****   **  ** **  **    ** **
 *   *****   ****  *  ** *   

 * * * *  **  ** *  *       *** * *   0;
}

Comments

prog.c: In function 'main':
prog.c:12:7: error: expected '(' before '{' token
     if{}
       ^
prog.c:13:12: warning: too many arguments for format [-Wformat-extra-args]
     printf("abc", &p);
            ^~~~~
prog.c:14:13: warning: format '%d' expects a matching 'int *' argument [-Wformat=]
     scanf("%d");
             ^

Answer 10

Hidden content!
  ** **     * ** ** *  ***
 * *  *  ** *    ** * * 
int main (){
char * **    
char *   * *** 
 *    **  ****   * * * * * **
* **** *  *** ** * *  ****   * **
**** ****  *    * *** ** *     
 **  ** ***     **** ***    * ** *  *
 ***   *  *    *** * * **
   * *  **  is a prefix of * ** ***   *** * **** 
}
else{
 * **   * **  is not a prefix of %s ***   ***** ** ** * *
}
  *  0;
}

Comments

prog.c: In function 'main':
prog.c:7:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string1);
         ^
prog.c:9:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string2);
         ^