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);
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   ***   *  ** * *** *** *** *   * ****    **      ***  **  * *  ** *  * * ** **    ****** * *** **  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()
{
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*    ** * ** ******** *  * ** * * **    * * 

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

* ***** * *       **
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return 0;

 }


if (i==plen-1)
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  **        * *** ****   *


}

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);
  *  * ** *****  *** *   **    **  **

 * *******  ** *****   *   **  ** *  * **** {
    ** ** * ** * **  ** *** * * *   ** *        *   * ***   *   *  {
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  * *   *  *    *** *** **
****  * * * *   **  *  ********  **** {
* *    *   * * ****  ***** *    *   * ** *** *   **  * * **** * * 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;
**      **  **   ** *****   
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*** **** * *      *  *  **  ****  * ***  * *
 *  **  * *  *     * *** ** ***** **** ** ****   * * * * *   *** 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;
****  * *    ***** ***   ***** *** * ******  * *  ** **  * *  * * **  **   ***  *****   **   *    *  ******
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* **  ** * *** **   *    *  * *  *   ***** ***   * ** 
    }
}

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