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