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