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