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