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