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