1.
Encryption in Rail fence cipher is done using . . . . . . . .

3.
What will be the time complexity of the following code which raises an integer x to the power y?
#include<stdio.h> 
int power(int x,  int y) 
{ 
	if (y == 0) 
		return 1; 
	else if (y%2 == 0) 
		return power(x, y/2)*power(x, y/2); 
	else
		return x*power(x, y/2)*power(x, y/2); 
} 
int main() 
{ 
	int x = 2; 
    int y = 3; 
 
	printf("%d", power(x, y)); 
	return 0; 
}

7.
Which of the following correctly defines poly alphabetic cipher?

8.
What is the condition for proper coloring of a graph?