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;
**   *  *** *   *** *  * * ***** *** 
* *   ****  * * ***  ***  **  ***    ** **
 * *  * * *   *** ** *  * * * * ***   
  ****  ** *** * ** * * * *     **   **  
    {
* *  * ***** * *****  **** *** ** ** ****  *** ** * ****  ** **  
 ****   * **  ** *** * *** **** *****  *  **** *    * 
* * *      *   *     *** *   * *   *  ** ****   *  **  *** *    ******* *** * *  * **** *  **  * 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);
         ^