#!/bin/python3

import sys

n, m, k = input().strip().split(' ')
n, m, k = [int(n), int(m), int(k)]
for a0 in range(n):
    row = input().strip()
    # Write Your Code Here
for a0 in range(k):
    i1, j1, i2, j2 = input().strip().split(' ')
    i1, j1, i2, j2 = [int(i1), int(j1), int(i2), int(j2)]
    # Write Your Code Here
print(0.25)