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;
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 *  **  ***   **  *** ****  *****  ****** **

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  *****    *    * * ** *    *

  ***    * *    *   
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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