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