1-11 Exercise 3: Prefix of a string

Question

4.3k 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 | 4.3k 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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}

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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];

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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];
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     * **      ******   * ** *  * * *   %s",a,b);
*     *   *** ** ** *** **  *    len = strlen(a);
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 *  *  * **   **  **  * *  * * * ** ***  ** * *     * ** ***   ******* *  * *  ** *    
 **   **  **   *        * ** *  ** * *** ***  

*  *  *  *  ** *   ** * ***
 ***  *******   * * *** * * *   * ** == 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
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 *****    *   * **** *** *  ** ** *  * *     * **  ***   **    * **   * ***  **** ** **  *  **** * ***** 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;
  *     ****    * * *   ** ***  ** * * ** **** 
  ***     **  * *** ** * *    * **   * *
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**    **    *** *  *  *      * **  
***   *        ** * * ** **   **
***   *  ***      **     *  ***    *
*    ** * ** *  ***** * ** ****  * *  *****  
***       **          * *  * ***  * * *** 
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 **** * **  * *   ***
  *  ** *    * *     * ***   ** *
 **  * *  **  * *      *  ****  **** ** *  *   **  **     ** ****** * * *** 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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