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);
         ^