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);
         ^