QUESTION

Given a integer x, write a function that multiplies x with 3.5 and returns the integer result. You are not allowed to use %, /, *.\n\nExamples:\nInput: 2\nOutput: 7\n\nInput: 5\nOutput: 17 (Ignore the digits after decimal point)\n\nSolution:\n1. We can get x*3.5 by adding 2*x, x and x/2. To calculate 2*x, left shift x by 1 and to calculate x/2, right shift x by 2.

ANSWER

#include <stdio.h>
 
int multiplyWith3Point5(int x)
{
  return (x<<1) + x + (x>>1);
}    
 
/* Driver program to test above functions*/
int main()
{
  int x; 
  scanf("%d",&x);
  printf("%d", multiplyWith3Point5(x));
  getchar();
  return 0;
}