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

 ** *  ** **** * *** * *   ** **  * * * * * ** ** i++)
* **  *****       ****    *

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

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