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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* **    * **   * * *  *

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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()
{

*** ***** ***   ***  *   *  *    a[100],b[100],c[100];
***   *** * ***** ** *** **** *  ********    **** ** 
    int l1,l2,i=0;
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* * * ** *    * ** *   ** *** * ** * 
** **    ****     *  **      ***  * * ***  **   *  ** * *   ** *  is not a prefix of %s",a,b);
    }
  *  *** **   ** ***    * * **      if(l1<=l2){
  * * * **  ** *   ***    ** * **  ****    * **** *** *  prefix = 1;
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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