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];
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** *** ** ******** *  ***        ***  * ***  * *   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!
  ***  *     * *  
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int main()
{
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*   ****       * *****  **    

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**** * ** *  is not a prefix of  *    *   *  *
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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*  *   ***  ******* *   *  ** ***      *** * * ** ** * 
  ** * * ****     * * * *** ** 
* *  ** ***   **  *** * *    *       {
**  ***  *  *       *    ** * *** * **   * *** **** ***    * 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);
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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