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