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