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