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