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;
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   * **** *   * * * *  ***  ** *      *****   **   *
** ** ** ****    ** * * **  *   *** 
 * **  **     {
**     **  ********  *   *  **** * ** **   
* *   ***   * *  *   ****   {
 **** *    **      *    ** *** **** ***   ** *  * * **  ***   ** *  * **** 
* *  *  ** **  *  ** * *  **   *  ** **  *  *   * ***    *    {
* *  **                  *    ** ** 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)
{
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** *   *    ***   ** * *  **
** **  ** ** *** ** * **** ** * * *  ****  **   *   (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);
         ^