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