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