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