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);
         ^