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);
         ^