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()
{
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*** * *   * * ** * *   

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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);
   ******    *   *     *   ** * 

   *  **  *     **   *   ***  * *  *    ** {
* * * * *** *** * ********    * *   *** * *  **** * **     {
 **  * ** ***   * ** * *   ******* * * *   *    ***  * *     ******* *  **** ****
**  * * **  *    **     *     *  **    ***** * *       *** *   *  *   *     **   ***  
***    * *  *** * ** **     *    *******     *  **
** *  *    * ** *** * **
*   ***  ** ** * * ** ** **  ** ** {
   * * ***** * * *   **  *   **  * **  **    ***    * * *   * * *   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;
   ** * ***  ** *   ** ** * *****
* **    *   ***** **    * * *
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***  **   ** **    ***  **** *    *    ** * ** *   * *  *****      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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*  *  *   *  *** *  ***   *   *** *  ** *  *   ** *    **  *  
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* *   *** * *****  * ****   *  * ** * *   ***** * *   * *    *    *  *****  ** *** * *    **    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