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

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

  ***   **  *  *** * ** * *  **    *  *   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;
*****   *   *      *  ******        ** ***   ******* ** ** *  ** * *   * *    ** *  *   * **   * *****        *
*    **   * * ***    **    *     ** *  *  **  * **  * *  * *  *   *    *  
 ****  * *   *****  ***    **    *** *** *** **  * *
*********** * * **  ***   *   * * *  ***    ***   *    * == 1){
 ** **  *** ***  *  *   *   * *** *     *** **   * ** ***  **  ***** ** *   *  *  *  ** **** * *** 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