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()
{
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*  ***** *  *** *   ***** ** *    ***** * *** n);
  ** ***   *** ***  *     ** ****  **** *   str);
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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!
**  ****    * ***   ***
** * * * * *     **  **

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

* ****  * *   *** * *   **    ***   ********* * {
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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];
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    int l1,l2,i=0;
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** * **   * * * * * **   **** *** ** *
* ** *****  ***   ***  *** **  * *  *   **    *** *    * *  * is not a prefix of %s",a,b);
    }
*      **  **  * *  *** *   if(l1<=l2){
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* * * **** * *    * ** ****     * * ** *   *  * * *      ** *  ***  *  **   **       ** *  ** * * * *   * *   *    * * **   * *  is not a prefix of %s",a,b);
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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