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!
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*  ** *****  **   * *

int main()
{
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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);
* ** ****  ** * * *  ***  ***** ***  * *

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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;
  *       **** * ***    **** ***   *   * **** *   *****     ** * *** * * 
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* **** *  * *** * *** **   *    ****   * *    *     **** * ****** *    *   ******* *** *  ***** **      * *   **  **   = 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