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