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