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