#include <stdio.h>
#include <stdlib.h>
#include <math.h>
int main(int argc, char *argv[])
{
   int n, i,j;
 float x[50], y[50], sumX=0, sumX2=0, sumY=0, sumXY=0, a, b;

 printf("How many data points?\n");
 scanf("%d", &n);
 printf("Enter data:\n");
 for(i=1;i<=n;i++)
 {
  printf("x[%d]=",i);
  scanf("%f", &x[i]);
  printf("y[%d]=",i);
  scanf("%f", &y[i]);
 }

 for(i=1;i<=n;i++)
 {
  sumX = sumX + x[i];
  sumX2 = sumX2 + x[i]*x[i];
  sumY = sumY + y[i];
  sumXY = sumXY + x[i]*y[i];
 }

 b = (n*sumXY-sumX*sumY)/(n*sumX2-sumX*sumX);
 a = (sumY - b*sumX)/n;

 printf("Value is: a=%f and \n",a);
 /*printf("\nEquation of best fit is: y = %f + %fx\n",a,b);*/

  return 0;
}