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