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