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