1-11 Exercise 3: Prefix of a string

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

 

Comments

12345

Answer 1

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

int main()
{
* ********  ** *    *  * * ***  * n[999],str[999];
 *  * *  * ** * ** *   *** **  *  * **  *     n);
*   ***** ** *         * ** ***** ***   ** ***  ** ** str);
 *** *    **** *    * *  ** * * *  ****      * * * *   ** *   * *  **  **** 
* *         ** *  ** * *  **    **   * **  *    *** ** *       * **    ** *   ***** * *** ***  **  is a prefix of %s",n,str);
**   **  *  **  *   ** ***** * * *** **   *    ***  
    * *  **   *  * *  **      ********* ***** **  *  *** 
 *  * * *   **  * ****  ***   ****  *  **** **   * *  *  *  *      *****      * ** *  **    is not a prefix of %s",n,str);
*      **    ** *  ***  **** ***    *  * * *  * **** *
* * ***  * ***   * ** *** *    0;
}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

---

-----------Re-judge-----------
Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

-----------Re-judge-----------
Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

---

prog.c: In function 'main':
prog.c:9:14: warning: format '%d' expects argument of type 'int', but argument 2 has type 'size_t {aka long unsigned int}' [-Wformat=]
     printf("%d",strlen(n));
              ^

---

prog.c: In function 'main':
prog.c:9:14: warning: format '%d' expects argument of type 'int', but argument 2 has type 'size_t {aka long unsigned int}' [-Wformat=]
     printf("%d",strlen(n));
              ^

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 2

Hidden content!
    *    * **** 
**      ** *   * *  **

int main()
{
 *      ****    ***  *****  * i,plen;
*** **   * *    *** *** **  ** *   *   *
    *******     * * ** *** *** *    ****  *   
*** ** *  *    * **** *** * *  ********   

*  **     ****  *   ******* *  *** **  *  ** 

  ** * ****   * ****    *     ** *** * *  ** *   i++)
***  *** *** *       *** * 

 ** ** ***  **  *
 *****  *
* ** *  ***** is not a prefix of  ** *** * * 
return 0;

 }


if (i==plen-1)
*   **     * is a prefix of **    *** ** 

**** ****  * *  * * ***  *


}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

---

-----------Re-judge-----------
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 3

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

int main() {
  **  ** *   *  * ***  * **  * p[1000],s[1000];
*  **** ***  *     ** ** * **   i=0,re=0,len;

   *** * *      ****   * * *  **  ***   * *   p);
 *  * **       * * **   **** *  ***  **   * s);
**** *  * *   ** **  *   *  **     * 

  *    ****  ***** *   *  ******       * * ** {
 *****      * ***** *   **     ***   *  ***     *  *** *  * ** *     {
    **    * ** *  ** * *       *      *    ** *   *** ***  * *** **  **   
*  *  * *** * **   **  ***      *      ** **  *****   ** *   * ** **  *   *** *** *
  ** *   ****    *  **  * * ** ** **** * * ***  ***
*     * *** * *** ** ** *
 ***   *  * ****      **   * ** *  {
   ****  ***  * * *** ***  **   *     ********* * **** *  ***  * is a prefix of %s", p, s);
  ****    *** ** * *  *  * *
******** *   * ***** * ****  if(re==1) {
  *    *  **   ***  ****  *  **      ****  **  * is not a prefix of %s", p, s);
    }
}

Comments

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

---

-----------Re-judge-----------
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[100],b[100],c[100];
 *** *  *    **  *   *  ***  ** * **   ** ** * *  
    int l1,l2,i=0;
 *** * * *  *       *  *   *    **  
 ******** ** ****   ***** * ***    *    
******   * *** * * **      **** 
**  ****   *** * ****** *     * ***   ** **  * *  *******   *   * is not a prefix of %s",a,b);
    }
**    *  * *  ** * *  **     * if(l1<=l2){
*  **    *  ** *   ** *   *  ****  **   *  *  *  *  ** *   prefix = 1;
    *  *    **     *   *  *** * * *  *  ***** ** *  ** **  * ****   
****   *** *  ****   *** *   **** *       *   *** ** *   * *  ** *  ** ** ** **  *    ** (a[i]!=b[i]){
   ****   ** *****  **** *  *** * *   ***  * *  *  * *  *   *  ***** * *** *** ** *  ****** *    ** *  * *  * *  ** ** * *  is not a prefix of %s",a,b);
 * * * ***  *** *   * *   ** *  **     *    *** *       * *   *   **  * *** ** * * ****** *   *   *** * *     *****    = 0;
  * * **   * * ** * * **   *** ** **  *  ***** ** *   **  ***  * *  * * * *    ***  *  *** *  **  *** ** **  * 
     * ** *    *   *** *    *   **   *****  * *  *    * * ****  *****    *   *  ** **  * 
*    ** *   ***   ****    ***   **** ** **  * ** * * 
 *****  * *   **** *  *  *** * * *  *     *     *  *  *  *  * == 1){
** ***  *    * *  *** * *   * *    *  ***  *   ****    ****** *   *   *   *** *  ** ** *  * **** ******* is a prefix of %s",a,b);
 *   * * * **** *** *     ***** *   ** ******** * 
    }
}

Comments

prog.c: In function 'main':
prog.c:8:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%s%s",&a,&b);
             ^
prog.c:8:15: warning: format '%s' expects argument of type 'char *', but argument 3 has type 'char (*)[100]' [-Wformat=]
     scanf("%s%s",&a,&b);
               ^

---

prog.c: In function 'main':
prog.c:7:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%s%s",&a,&b);
             ^
prog.c:7:15: warning: format '%s' expects argument of type 'char *', but argument 3 has type 'char (*)[100]' [-Wformat=]
     scanf("%s%s",&a,&b);
               ^

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

---

-----------Re-judge-----------
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 5

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

int main()
{
  *   * ** ** * *  *  **    prefix[100];
*** * *   *  *     * *********  ** word[100];
****  **  **   ****  *   **    * %s", prefix, word);
 * ***  **  ***** **       **** * i;
   *    * * ***   **   ****    = 0; i< strlen(prefix); ++i)
** * **    * **  *** *  ****
*  *     * **   * *      *   **    * ***    * ****** *  ***
   *   **   *****  **  *  **    *******   * ** ***
***     *  ***     ** ***   ***  * *  * **   *  *   * ***    ***** * *** * *****  ** **  ** ** ***  is not a prefix of %s", prefix, word);
   *    ** ** ** ** ***** **   ****   ** ** * *** * *** **       *    ****  * * 0;
 * * ** * *** **** *  *** * *******  **  * * **
***       * *   *****  
* * ** **** **** ** * * * * *     * is a prefix of %s", prefix, word);
 * *  * *   ********** *** *    *  0;
}

Comments

prog.c: In function 'main':
prog.c:15:12: warning: zero-length gnu_printf format string [-Wformat-zero-length]
     printf("");
            ^~
prog.c:17:12: warning: zero-length gnu_printf format string [-Wformat-zero-length]
     printf("");
            ^~

---

prog.c: In function 'main':
prog.c:15:12: warning: zero-length gnu_printf format string [-Wformat-zero-length]
     printf("");
            ^~
prog.c:17:12: warning: zero-length gnu_printf format string [-Wformat-zero-length]
     printf("");
            ^~

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 6

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

int main(){
***  *   * **  *  **  ***  ***  p[100],s[100];
*****   *     *   **   ** **   ** * * **   *****  
**  ** **  *** * ******  ****** * bf=1;
   * * * * ***  * ** * ***** *****  ** ****  ****     
* *  ** * ***      * **** ***   ***  ***  **  *  *    ** *** bf=0;
** **  * *   * * *** **  *

*** ** **   * *** * * * *   **** *  * **   is a prefix of %s",p,s);
*****   ** *** *     *    *  **** ******* ** ** is not a prefix of *     * ***
***  *** ***    * *       *  0;
}

Comments

prog.c: In function 'main':
prog.c:5:5: 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:6:5: 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:8:19: warning: implicit declaration of function 'strlen' [-Wimplicit-function-declaration]
     for(int i=0;i<strlen(p);i++){
                   ^~~~~~
prog.c:8:19: warning: incompatible implicit declaration of built-in function 'strlen'
prog.c:8:19: note: include '<string.h>' or provide a declaration of 'strlen'
/tmp/cclwPOj6.o: In function `main':
prog.c:(.text+0x26): warning: the `gets' function is dangerous and should not be used.

---

prog.c: In function 'main':
prog.c:8:19: warning: implicit declaration of function 'strlen' [-Wimplicit-function-declaration]
     for(int i=0;i<strlen(p);i++){
                   ^~~~~~
prog.c:8:19: warning: incompatible implicit declaration of built-in function 'strlen'
prog.c:8:19: note: include '<string.h>' or provide a declaration of 'strlen'

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

---

-----------Re-judge-----------
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 7

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

int main()
{
   * *   *  * **    *   * **   i,count=0;
**  * * **** *  ** **  **  * * *  * string1[100];
*** * ** *  *** * *** *  **  * string2[100];
   ** *      ** * ****  *   **  ****** *  * ****
 ***** **  **    *      *  **  *            **    ** * 

*   **  *  ****  *  **** *****  **** * **
*****  ***  * ***** ** **   
  ***   **** * ***** ** ***  **** *    * *  ****   ***     * *****
** * *           *  * **   *  * ** * ***    
 *    ** *** *  * *  *** **** * *****      ** ** **     *   *    ** *    * * *  * ***
*  * * * *           *  ** * * * * * * ** * ** * *** *  
    }
   ***  ** *  ** *    * *   *
 ** *    * * **** ***  **   ***
**      * **   *** * ***   * *    **      * * *      * *  * *  is a prefix of %s",string1,string2);
    *     *     **  **     **
  * * * *  ** *** **  **    
*** **   *********  **  ****** 
 *  *** ** *** *  ** **** *    ***** * *     *   *  *  ****  * *   ***  is not a prefix of %s",string1,string2);
* ***   * *** ****** ****** * 
 *  * **   *      * * *** *  *    0;
}

Comments

prog.c: In function 'main':
prog.c:9:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(string1);
     ^~~~
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:10:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(string2);
     ^~~~
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/ccIBxtbQ.o: In function `main':
prog.c:(.text+0x2f): warning: the `gets' function is dangerous and should not be used.

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

---

-----------Re-judge-----------
Case 0: Correct output
Case 1: Correct output
Case 2: Correct output