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