#!/usr/bin/python3

def numerical_shitty_integration(func, n, a, b):
	epsilon = (b - a) / n
	result = 0

	for i in range(n):
		result += epsilon * func( a + epsilon * i)
	return result

if( __name__ == "__main__"):
	f = lambda x: (1 - x**2)**0.5

	print(numerical_shitty_integration(f, 5000, -1, 1))