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