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!
     ** *****     
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int main()
{
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* *   ** * * ** * 
**  ** *
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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);
  * *    * * *  *   *   *  * *****  

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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()
{

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 *     * *  * ***    * *  **   * *   **  * **** *
    int l1,l2,i=0;
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* *      ****   * ******** *   **** 
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* * * *  *  * * *   ** ***** ***  ****** *** ****** *     * *  * is not a prefix of %s",a,b);
    }
*  **  *    ** *  **  *** * if(l1<=l2){
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   *****   **** **  *   * ** * *   ***     *** ***  * **  * *******  ** * **** ***    * *     * *  **   ** * *   **** * is not a prefix of %s",a,b);
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*     ** **     * * **** ****** *** * ** ***** *     
    }
}

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