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);
         ^