Final Exam 2 (20%)

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

 

Answer 1

Hidden content!
    ****  *  ** ******* 
    *    ** **** *  * *

int main()
{
**  * ***     *  char     *
  * * *      int i,c=0;
*         *** * *  **     *  * ** *  * *   * 
     **** *    **  *   ***   *** *    **  *  *   
*  * ***** * * ** * ** **  * *  * * ***  
* *    **  ** * * {
   *   ***** *   **     *   * * ****
*  * * * * *** * *  * * ** *   ** {
* *  **  *      * **    ** *   *  * *  **  * * ** *     * *  **  ***  ** 
*   *   *  *  *  *   *     **   *  * * *     *   * *   ** * {
                   ******* **** c=0;
* ** *  *   *  *  **  *****    * *   * ** ***    * * **   **  }
* ** **    ** *   **      * **    ***** *     * else  *****   ***   *    **  
*    *  *   ** *   **  * *     **     **  * **  *  * * * {
  ** **  ***   * * *  **    *   * ** *  ** *      *** *     * ***   * ** * c++;
 **   * * ** *   *    * *** ** * **  * *  * * *  *    *    * *   * }
 **  *     *       ***  ***  * }
 *  **   **  
*** * * *  ** * if(c==0)
*   **   **    ** *        *  **** * * is not a prefix of     * *  *
 **  *  **  else
  *  ** **  *  **  ** *** *   *   *  *  * **    is a prefix of  ** * * ****
** * * *   * **    }
   **   * *     * return 0;
}

Comments

prog.c: In function 'main':
prog.c:8:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&a);
           ^
prog.c:9:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&b);
           ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

prog.c: In function 'main':
prog.c:10:6: warning: implicit declaration of function 'stlen' [-Wimplicit-function-declaration]
   if(stlen(b)>strlen(a))
      ^~~~~
/tmp/ccnE3ufV.o: In function `main':
prog.c:(.text+0x5b): undefined reference to `stlen'
collect2: error: ld returned 1 exit status

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Correct output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 2

Hidden content!
**   ** ** *  **** ** *  
 *  * * *   * ** *   
int main()
{
* * ** ** **** ap;
*    ******   * * ** ***  * ***  * ** * **     || ap=a)
   * * *** * **  *  * **** * **  ***   * is a prefix of abcde\n");
 ****     * **  * 
**  ***  *   
* *  *  *   ***   * *   * *  * **  **  *  is not a prefix of abcde");
 ***    ****     ****  ** **  ***  * ***  *  *** ** ** ** *  *** *  ** *    ****  * * 0;
  * ***    **  * ******* *   * * *  ****      ****   *  *      * *
  

Comments

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

Answer 3

Hidden content!
  *** * **    *  * 
***  *   **   *

char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
*****  *** *     ** *  ***   *  i<pl; i++)
 * **   **  *  *  * *  * *  
*  * *** ** * *  ***  *** * **  *****   *  *   *** *    (p[i]==s[i])
**  ** *    ** *  **  ***  **** *    **    **  * 
* ** ***     * *   *   * ** ***    ******* *   **  *  *  *          **** **   * *  
* *****   **** ******   ****   ** *** ***  * **  **   ** *    ***   *** ** *** **
**  **   *  **   * ***** ******* *   *      * *  * *  ****     * **** *   * ***  ****  * *   ** *   * ** 1;
  * ** ** *   * ***  *****  *  * ** ***  ****  *     ** *  * *****  ***  * *    *** ****
   ** ** *** * **   ***  * ****  * * *  ** ***** *
    ****  ***** ** *  ** * ****  **  * ** ** **** *  * **  **  *** if(p[i]!=s[i])
 ** **     *    ******   ** *****   * * **** **** * 
**    ** * * *** *  *** ** ***    * *  * * * **   *     *** **   *      ** 0;
    * ** * * * *  **** ** * ** **** **   * *  **   ***  * *
*****  ** ****  * **  *    
}


int main()
{
* ** * * *  * *
 **  ** **** * * **
   * ***   ***  ",p);
 ** ****** *  *****
   **   ********   * 

sl=strlen(s);
pl=strlen(p);


  ***    ** **  * && pl<sl)
{

  * *   *  **    *   *  ***  **  **  ***    is a prefix of %s",p,s);
}else
{
printf("%s is not a prefix of %s",p,s);
}





}

Comments

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

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[99],b[99];
    int l,i;
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 *** **  *  ** ** ** *  *** **  **   
** * *  **** ******   *       ****  ***
  ***** *****   *****  * ****    **  **  
    {
* **    **  * **** *    ** * * **** *** *  ***  * ** * *   * * **
*** * *  * *** *   * *** *   **  **** *****  *   ** 
**    *  *      * ** ***** *  ***   *  ** **  *** *  ** *  ***   *  ******* * * **   ***** *  *  * *  *  *** a prefix of %s",a,b);
***   ***** ***    *  ****   **********   *  **   *  * **  *****  ******* ***
*   * ****** * **  ***  *   *  * *    ** *  * ** **
** *    *** * * ** * *   ***    * *  *   ***  ***  *****  ****
*   *  *** ******   * *    *   *   * *      ***  ***  
  * * *  ** *  *   *    **    * * * *** **   ****  * * * *** * **  *   *  * *  *******    * *   not a prefix of %s",a,b);
    ***    *   * *****     * *   ***** *  *  **  ** * ** ** ** * * **   *     *** ** *
**   ** *    * ***  ***** * *  *   ****   ** * *** * * *   
    }


}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 5

Hidden content!
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

int prefix(char a[100],char b[100]);


int prefix(char a[100],char b[100])
{
  ***** *  ***** ****      i;
   *   *  ***  ***  *   ****    ** count=0;
   ** * *****    **       * len;

 ** **   *** *  *  * ***  * **   ** 

**    * *   ** * ***  *** **** **      *
***** **   *  * ** **
 *    * *** **  ***** * **  **  * * * * *** * *  ** **   ** ** *
* * *  * **  * **** * *  **   ****** * ***    **  *
   * **     **** * **** *  * *  **** *** * *   *   ** *** *****     ***** **** 
 **  * * *        **** * *   * ***   *  * * * * *    *
  * * *    *** ** ** *** * *  


   *** *       ***  *** ***  *  
*** * ** ** *     **   ** ** *
     ** ** ****** * ***  **  * **  ********  **** ** *  *** 1;
 *    **  **   * **  **  *
**** * ** **  **** *  * *    * 

   return 0;
}


int main()
{
  * **  * **  *****   ** ** ***** *  a[100];
 * *     *****  **  * * **   b[100];


* ** **      ****  * * ** * ***  ** **    **  * *  ** * **
  *     * ** **  ** **** *    ** ****  **  *  ** ** * **  **  * *

*** ** ******  ** **** *   **  ***
 *   ** * **** **** **  *    **  * * ******

**       *** ****  ***  ** *****  *  

 {
 **   *****     ***** ** *******  *  * * **** * ** * **** ** ** ** is a prefix of %s",a,b);
*   **  **  ** *       * *** 
***** * ** ** ***     *** ** *
* **  * ** *  * **  *** ****  *
  * *   *  * * **  * ***   **  ****** ***  * *  * ** ***      * * *** * **   *    is not a prefix of %s",a,b);
  *      **** *  **     *  ** *


* ****** *****    ***    ** * * *   0;
}

Comments

prog.c: In function 'main':
prog.c:45:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&a);
               ^
prog.c:45:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&a);
                    ^
prog.c:46:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&b);
               ^
prog.c:46:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&b);
                    ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 6

Hidden content!
  * **  **  *** * **  
  *  *  * * *** 

int  *  *
{
 *     ***   *** ***  * * * *    ** **  no idea, I *** *** even do it in the   ****  *****
* ***  *** ** * *  * *  * **  0;
}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 7

Hidden content!
#include        * ***
#include *   ****        * *
#include  *  *   * ** 

int pref(char[],char[]);

int main(){

 ** ** ****  *    * * *       * p[10],s[10];
* *  *  **** *   **  * *****  num;

 *   *** **  * * *** *     ** * ****  
 *  * * *     *  * **** ***  ** *    
* * * * *    ** *   *****    * * ***** * * *   *    * * 
 *  ****  *    * **  **    ****  *** *    * *  **  * * *

*  ** **  * **   *  ** * *** * = pref(p,s);

 **   *    * **  * ** *** **  ** 
 * *** **** * * *  *  * *  *  **  **** * ***  * ****    ** **  is a prefix of %s",p,s);
 **  *** * * *  *****  *  * ***  ** 
*   **  *   *** **       * * *  ***** * ***     ** *  *  **  *    * is not a prefix of %s",p,s);


 return 0;
}

int pref(char p[30],char s[30]){
  *  *  *** * *     * * ** * i;

  * *   *  **  ****   ****** ** *****   ***  ********  
  ***** *  ***    *  *    *  *  ***   *  ** * ** *  *** *  *   ** *  **    ** ** ***    *   *  * *    *  ***  * ***
 ** * ***** *** *  ****** * ***  *  *  ***  *  **   *  * **  * ***    *   *       *     ****** ***  ** is a prefix of %s",p,s);
*  ** ** * * ***   **  *  *   *  ***     ****** ***
** ** ** ******** **   ** *  **   *        *   **   **   *****  * **  *    ** * * * **   *****   is not a prefix of %s",p,s);

  * * **     * ** * * ** 

}

Comments

prog.c: In function 'main':
prog.c:12:5: 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:13:5: 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__;
              ^~~~
/tmp/cc0tBG5r.o: In function `main':
prog.c:(.text+0x1f): warning: the `gets' function is dangerous and should not be used.

---

prog.c: In function 'main':
prog.c:10:13: error: stray '#' in program
     int num;#include <stdio.h>
             ^
prog.c:10:14: error: 'include' undeclared (first use in this function)
     int num;#include <stdio.h>
              ^~~~~~~
prog.c:10:14: note: each undeclared identifier is reported only once for each function it appears in
prog.c:10:23: error: 'stdio' undeclared (first use in this function)
     int num;#include <stdio.h>
                       ^~~~~
prog.c:14:1: error: expected expression before 'int'
 int pref(char[],char[]);
 ^~~
prog.c: In function 'main':
prog.c:23:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:24:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^
prog.c: In function 'main':
prog.c:51:5: 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:52:5: 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: In function 'main':
prog.c:14:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:15:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^

Answer 8

Hidden content!
** ** ***** *   **** **
*  ***  ***** * ** * *  

int main()
{
**  *  ** length1,  **  c;
**  *  ** *  a[100];
***    b[100];
   * ** *  d[100];

* **  ** *******  * **** ***  *   *
* **** ** ****** ****** * *** ***  

* *  *   *****  ****

 *  ***  * *   ***    * *

     ** **  *   
*   ** 
** ***   * * *  *       ***  is a prefix of  **  **     
**** **  
 *  ** **   * **
  * ** *
*  **   *       is not a prefix of  **  * *    
  *** *

}

Comments

prog.c: In function 'main':
prog.c:11:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&a);
          ^
prog.c:12:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&b);
          ^
prog.c:24:11: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
           ^
prog.c:24:33: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
                                 ^

Answer 9

Hidden content!
  ** ****  * *** **  **
*    *  * *   * ** 

int main()
{
 **    * * * *     * *  *    *****  str;
* * ***    * ****     *  ** **  ** i, p, s;

*** * * *** ***  * * *  ****** * *  ** * ***   *  &p, &s);

*      **    **  *****     ** (i<=0; &p; i++);
  * ** *    *  ** ** **  **    
*    * * ***  ****   *** * *  **  *  ** * **  &p);
* * * * ****  *  * **** **     * *** ** *   * *  *
* ** * *** *   *    *     
***  *     *  *  * ****** * * 

   * *** * *** **** **** ** ** * 0;
}

Comments

prog.c: In function 'main':
prog.c:12:7: error: expected '(' before '{' token
     if{}
       ^
prog.c:13:12: warning: too many arguments for format [-Wformat-extra-args]
     printf("abc", &p);
            ^~~~~
prog.c:14:13: warning: format '%d' expects a matching 'int *' argument [-Wformat=]
     scanf("%d");
             ^

Answer 10

Hidden content!
 * ** ** **   *    *
*** *   **   ***  ** * 
int main (){
char  * *   
char     * * 
*** ** ****** ** *    **  
 *  **  ****  ** *     *  **  *     
** ** * ***  *    *   *  ** *    *  *
*  ***** ** *         * **    
* ****    **** *  *   
  **   *  *   is a prefix of  * * ***     ***  
}
else{
 ***** * *   ** is not a prefix of %s  ****     *   ***  *   
}
 *   0;
}

Comments

prog.c: In function 'main':
prog.c:7:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string1);
         ^
prog.c:9:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string2);
         ^