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