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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 *  *    ** * *****  * * **   **  *  ** ***  **    * 
 **** ****   *   *  *   * ** * 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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return 0;

 }


if (i==plen-1)
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}

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;

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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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    }
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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)
**      **  *  * * **** *
* ***    ** *  *  ***   **  *  *    **   *** ***   ** ** **    
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   ** ***  *   * **** * * * *      * *  * ** *   * ** *   *   * **   ***  ** ***** *  *   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];
** ***** ****  **  ****     ** ** *** *** ** *  * * *
  **** **** * **   * *   ** * *  ***  *  *** *** ** * * 

*    *     **   ***    *   * **     **  **
 **     *     * *  ***    *
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 *  **** ***** * *** *  ** ** *  ** ** **  *  *     ******     *  **   **  ***** **
  * ***          *** ***    *    *  *   *        *   ****  ** 
    }
  * * *****    ** **  ** * *  *****    *
** ***    *    * ** *
  *   * *   * *  * ******** *  ***    ** **   **   *      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