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);
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 *****  * **  * * ** *     * ** *    ** *   * *   *   *** ** ** **  ** ***    
  **** ****** * * * ***      *   ***** *   *****  * ***    * ** *  **   *  * *  **  **  ** ** 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!
* * **** *  *** **
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int main()
{
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********* **  ***  ***     ** * * * ** *  * i++)
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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);
****  * ** * ****     * * * * ***   *

**** * **  *  *** **      ** *   **** ***   ** {
*  * **  * ***  * ** * *  *    ***     *  *     *   **** ** ***  {
  ***   *  * * **  ** *  ********   *           ** *** *** ***   ****  *    **
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*  **  *    * *** * *    **  *******  * * *  **  
***  *  *   * *    *  * * 
**   *      ***     ***  ***  **   **  {
  *  ** **** ******  * * ****  ******   **  *   **** * *  * * **      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;
*  * *  * *   **  * ** *  *  *  ****** * *  *         **     *      * **** *   *    * ** * *  *** *     * 
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*  * ***** ** ****  * * *  *  ***   ** ******  **  *  *
    }
}

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