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