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);
 * * *   ** ***      *   *   

** ***  *****  *   * **    **  *  ** ** {
  ** * *   *  **   *** * * * ** * * * *  *          * **  {
*   ***  *  **  * *  * * * ***  * * ** ** *   ** * **    *  * *  ** *  **  **** **  
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  * **  * ****  *   ***    * ** * * * ** * *     * *   **   
 * ***  *  *  **** * *  **  * *
*  * *     *  **      *      {
* ***  *  * * **     *** *     **** *   *      *  **   ****** **   ** 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