1-11 Exercise 3: Prefix of a string

Question

10.7k views

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

[Exercise] Coding (C) - asked Jan 11, 2018 in Chapter 13: Strings by thopd (12.1k points)
ID: 41439 - Available when: Unlimited - Due to: Unlimited
edited Jan 11, 2018 by semicolon | 10.7k views

27 Answers

Page:

Diyiel · Answer 1 · 2018-01-13 00:58:32

Hidden content!
#include  ** **  ***  ** **
#include  ****** *  *** *

char prefix(char s1[], char s2[])
 {
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answered Jan 13, 2018 by Diyiel (-193 points)

Stephen Richards · Answer 2 · 2018-01-13 00:46:20

Hidden content!
#include * *   ***
#include *****  *  *** * 

int prefix (char st1[],char st2[]){
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}

int main(void) {
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}

answered Jan 13, 2018 by Stephen Richards (323 points)

ryan · Answer 3 · 2018-01-11 22:07:28

Hidden content!
#include<stdio.h>
#include<string.h>

int main()
{
    int i,j;
    char a[100], b[100];
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}

answered Jan 11, 2018 by ryan (-301 points)

Headshake · Answer 4 · 2018-01-11 21:22:34

Hidden content!
#include<stdio.h>
#include<string.h>

int main(void)
{
    char pre[100], str[100];
    int i;
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}

answered Jan 11, 2018 by Headshake (-281 points)
edited Jan 13, 2018 by Headshake

Sabrina Lin · Answer 5 · 2018-01-11 21:03:22

Hidden content!
#include <stdio.h>
#include <string.h>

int main()
{
* **  **   ** **   **** * a[100];

 *  ** * ***  * **** *  **** ***  b[100];

*      ***  ***   *** *   i = 0;

****        *   *   ** *   *** prefix = 1;

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**** ****   ***   * * * *  *   = 0; i < len; i++)
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}

answered Jan 11, 2018 by Sabrina Lin (-285 points)
edited Jan 11, 2018 by Sabrina Lin

watty1998871108 · Answer 6 · 2018-01-11 21:00:46

Hidden content!
#include  * ***** **  ** 
#include ***  ***   *** *   * 

int main() 
{ 
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*** * ***   * *  ****  *   *  *  0; 
}

answered Jan 11, 2018 by watty1998871108 (-127 points)
edited Jan 17, 2018 by watty1998871108

prog.c: In function 'main':
prog.c:8:5: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
     scanf("%s %s",a,b);
     ^~~~~
prog.c:8:5: warning: incompatible implicit declaration of built-in function 'scanf'
prog.c:8:5: note: include '<stdio.h>' or provide a declaration of 'scanf'
prog.c:15:13: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
             printf("%s is not a prefix of %s",a,b);
             ^~~~~~
prog.c:15:13: warning: incompatible implicit declaration of built-in function 'printf'
prog.c:15:13: note: include '<stdio.h>' or provide a declaration of 'printf'
prog.c:21:9: warning: incompatible implicit declaration of built-in function 'printf'
         printf("%s is a prefix of %s",a,b);
         ^~~~~~
prog.c:21:9: note: include '<stdio.h>' or provide a declaration of 'printf'

commented Jan 17, 2018 by The Judge (4.3k points)

prog.c: In function 'main':
prog.c:8:5: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
     scanf("%s %s",a,b);
     ^~~~~
prog.c:8:5: warning: incompatible implicit declaration of built-in function 'scanf'
prog.c:8:5: note: include '<stdio.h>' or provide a declaration of 'scanf'
prog.c:15:13: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
             printf("%s is not a prefix of %s",a,b);
             ^~~~~~
prog.c:15:13: warning: incompatible implicit declaration of built-in function 'printf'
prog.c:15:13: note: include '<stdio.h>' or provide a declaration of 'printf'
prog.c:21:9: warning: incompatible implicit declaration of built-in function 'printf'
         printf("%s is a prefix of %s",a,b);
         ^~~~~~
prog.c:21:9: note: include '<stdio.h>' or provide a declaration of 'printf'

commented Jan 17, 2018 by The Judge (4.3k points)

Sammi0208 · Answer 7 · 2018-01-11 21:00:08

Hidden content!
#include <stdio.h>
#include ** ** * *  * *
#include ** ** * *  *  ***  

int main()
{
** **    *** ***     * * * a[100],b[100];
  **   *  *** **** *   * *   ** i,j,prefix = 1;
*    * **  *   *  *   * * * *  *   * %s",a,b);
** ** * * *  *  *    * ** len = strlen(a);
 ***  * * **   ****  *** *** ** = 0 ; i < len ; i++)
 **  *   *  *       * *****    ** 
 ***  ** * **** **  *****  *  ***   * *** *  ** * ** != b[i])
*      * *  **   *  *** **  *   * *  ** * *** **  * * ** 
**   ** *    ** ***** ***  ** **    ** * *  ***   * *     ****     * **   **** * *** *** = 0;
   ** ** **   **   *   * **** *   * ****  * *     * *   **  ** * ***  *   **  **  **  *  is not a prefix of %s",a,b);
* ** *    *  **** *    *   * *  **** **  ** ** **   * *** **** * *  * ********* 
* ** ** *****    * * *  * * *   * **    ***** *        ***

** *   ***** ******* *  *
*** * *******  ** * **** * *   *    == 1)
* **  * **   *  ****** *    * *****  **   *        ******      ** ** * is a prefix of %s",a,b);


*  ******  *   *** **   * *  *   * *  0;
}

answered Jan 11, 2018 by Sammi0208 (-255 points)
edited Jan 11, 2018 by Sammi0208

410530022 · Answer 8 · 2018-01-11 20:46:02

Hidden content!
#include   *  * **** * 
#include ** ***  *** ** 

int prefix(const char *pre, const char *str)
{

*** *** *** * ***   **   *****       ********  ** *
   **   ***  ***         * *** **     ** *   ***  *  **  **** 0;
** *   *  *** *  *   * * * * *** ****    * *   * *  **
  *  * **   *******  * *** * ** * *** * *  * **  **      1;
*  *** *   **   ***      ***   ** return 0;


}

int main()
{
  *    * * ** *  * * *  *  ***** pre[100],str[100];
   ** ** * **   ** **** 
**    *    *  ** **      **  * *  ***** *****
   *    * *  *   **** * * **   *  *****   ***
 *  ** *  * **  *    * * ******** *** ****  **           ** *** is a prefix of %s",pre,str);
 ** *   ****   ***** ** *****  *
 ** * *   *  * *  **  * * ** * ** **   **      **   * * *  * *   ** * is not a prefix of %s",pre,str);
*   ** ***     *  ****  *  0;
}

answered Jan 11, 2018 by 410530022 (-196 points)
edited Jan 11, 2018 by 410530022

LinJingYao · Answer 9 · 2018-01-11 20:28:50

Hidden content!
#include <stdio.h>
#include <string.h>

int perfix(char *a,char *b){
*  *    * * *  ** * *    * * ** c;
*  * *  *  * ** * *  * ** * *******  * ***    *
*     * *** *     * *** *** *** *   ** *  *    * *   *    * 0;
 *   *    **   ***  * **  * ***  
  * ***  ** *  *** ***    **  
* ***   *  **    *** ** *   *       *   **  *   **  ** * *  * ******** ****   **  *   of a string
 *  ****  * **** *   *   ** *  *** **  **   * * *  *    *    ** ** ****** *    * * ***
       * *  *  *** *   ** * * *       * ***** * *** ** ***  ****        ***   * ****  * *** *  *   *     * *  *   *** 0;
*  * ** *  *  *         **  * *  *  ** * * * ** ***  *  *    
 *   **         *** **  **  *** *   *     ********** * * * 1;
    }
}

int main(){
      * *   ** * * * *  **  *   a[100],b[100];
*** * * * *  * ***  *   *    * *** *** *** %s",a,b);
*****  ** *** **  ** * **       ** ** *  **   
* ****  * *   * * *  * *   * **   *  *   * **** *   *   * ***   is a prefix of %s",a,b);
    *  ****  *  ***** 
**** *  * ** * *     ********     *  ***   *  *****  **     * * is not a prefix of %s",a,b);
 * * **    *   **  *  *  **     0;
}

answered Jan 11, 2018 by LinJingYao (-498 points)
edited Jan 17, 2018 by LinJingYao

VincentXV · Answer 10 · 2018-01-11 20:05:37

Hidden content!
#include <stdio.h>
#include <string.h>
int main()
{
 *     * **** **   **     *  * p[100],s[100],a[100]={};
***  *    **       * **   t;
* ** * *** **  ** **    *  * **** * *  **** *
  ****** **  ****   ** ***   ***** * ** ** 
* ***   * ** *** * * ** * * * * ***  ** %s",p,s);
  * * ***  *  * **  **      *  * **
   ** **  * ** **  *****   *         
**    *    ***  **  *  * ***** *** 
     **    *** *** **  *    ** *****   **  * 
  **  ** **   ****   **** ****  *** 
** * *    * **** * *  * ***   *        *  *     *    *   * *  * is a prefix of %s",p,s);
** *  ******* ** * * *** 
 *   ****  **  * * *  ***  **
     *** * **   *** **  *    ******  * * ** * ****    ***  ***** *** * *** is not a prefix of %s",p,s);
    **    ** * * *    * ***
 *   ***     **  *  **  * ** 0;
}

answered Jan 11, 2018 by VincentXV (54 points)

1-11 Exercise 3: Prefix of a string

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