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