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