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;
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****  * **  **  **   *   **      *** * *** *  
* **** **   **  ***     ** **     *** **  

*   ***** *** ***  * *  *  ****     **  *

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  ** ****   ***  *    * *

 ****  **  *   *
  * **  *
 ** *** * *  *  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);
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***  * ****  * * * **  *  *****

***** *   **  *   *    *   **  ** *  * {
  * *  *  *    ****   * *** * **   *   *  *** ***    *  * {
*  *    *** * ***  * *** * **     ***   * *    * * *********** * **  *** ** ** * * * **     *  *
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* ** ********   *  *  *     * ** *  *** **  ***** ** 
** *        * *** * *** 
  * *     ********   *  *   {
*     *  ** *  *****  **  *  ** *   ***  * *  *    **      ** * 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;
 ***  **  *  * *  *  *  * ** *   * * *   * ****  *   *  ** *   ***  **  *  ***** ** ***  * * * *   *** *** ***  * *
* ***  **    * * ***     ** ** ******    **  * *   * ******  * * *   **** ****  *
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***** * *  * *** *** *    ** *** *       **   ********* **** **  ** ****  **** *** ***    *    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