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