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

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

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