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

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

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

 * **   ** * ***   **
 *  *  
  * ** *** is not a prefix of  *    * * 
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