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()
{
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 *   *   **   * * ** *     *   ** * *       **   *
 * ****  ** ****  *  **  **** * ***   * *  
  * * *  *** *** **   ** **  *  ** ** ** 

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

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