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;
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*  ****  * *** *  * ** * * **** *** * * * *

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***  *  *  **         ***  ***

 ****    * *** 
*    
* ***  * *** 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