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