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()
{
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****   * ***  * *** * *    ***  *   **** **     *    n);
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 * * ***   *    *   * ** **    * *** *  *       * * ***  *****  **  *  **  * *    **  * * ****  is a prefix of %s",n,str);
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    * * * **    *   *****      *  ** *  *****   ** **     ** *  * *  * *  * * *   **  *  * *  *  * 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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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;
**** **  *       ** ** *   ***  
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***  ** * **** **  * * ** ***  *    * * *  
 **  *  ** ***   ***  ******      *  * * **  *      *** ** * *****   is not a prefix of %s",a,b);
    }
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** **   *   * ****** *    * * * * *****  ***  *   prefix = 1;
***  *** *     * *  ***  **     ***  *** ** ***  ******      *  ** ****    * 
  **  *  * ** * ****  *   *  * *  ** *   ******    *  ** *** * ** ***  ****  *  **    *  (a[i]!=b[i]){
** *   *  ***     * *    *  ** *  **  *  *  *  * * * ***  *      * * ***** * * ****** *    ****       * *    *   * *** is not a prefix of %s",a,b);
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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)
*  **    *** ***    ** *** *
*** * *     ***     * * *   *       * **  ***  *  * * * * 
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  **** **  * ****     ** ***** ** **   **  *   ** * *  * *    * *  *** *** ** *** ** *** ** 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