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