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