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