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);
         ^