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

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

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])
 *        * *  * *** * ***    ***       **    
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  ** ***  ***   **   **  **   * **     *  *** * *  ** ** *   ** * *** * ** *  
*    ***  * **    *** ***** ****  ** ***** * *  ****  *  * ** * *   * * *  ** **  **  *    * ****  *  **    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);
         ^