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

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