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