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);
         ^