def max_sum_of_three_consecutive(arr, n):
	 
	sum = [0 for k in range(n)] 
	if n >= 1: 
		sum[0] = arr[0] 
	if n >= 2: 
		sum[1] = arr[0] + arr[1] 
	if n > 2: 
		sum[2] = max(sum[1], max(arr[1] + arr[2], arr[0] + arr[2])) 
	for i in range(3, n): 
		sum[i] = max(max(sum[i-1], sum[i-2] + arr[i]), arr[i] + arr[i-1] + sum[i-3]) 
	return sum[n-1]
def min_cost(cost, m, n):
	R = 3
	C = 3
	 
	tc = [[0 for x in range(C)] for x in range(R)] 
	tc[0][0] = cost[0][0] 
	for i in range(1, m+1): 
		tc[i][0] = tc[i-1][0] + cost[i][0] 
	for j in range(1, n+1): 
		tc[0][j] = tc[0][j-1] + cost[0][j] 
	for i in range(1, m+1): 
		for j in range(1, n+1): 
			tc[i][j] = min(tc[i-1][j-1], tc[i-1][j], tc[i][j-1]) + cost[i][j] 
	return tc[m][n]