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++)
*** *  ****  ***  *     * ***
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*** *** * **** ** *** ** **** * **  ** *   ***  ***
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***  * ****    * * ***  ** * ** **     * *****  * ** **     * * ** *   **   ******
*      * *****  * * *   * ** *** ***** * ***   *  ** *
*******  * *  **  **** ***  **** ** *   *  ** ***   **** ** * *   if(p[i]!=s[i])
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** ***** * ***    * * **    **   **  * * * * ******   
******    ** * *      * *****   
}


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()
{
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    int l,i;
* ** **   *   *** **  **   *    *  * 
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**** *  **   *  * *** *  * *  *     
 * * *  **** ****      * * * ** ** *   *
    {
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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);
         ^