def check_expression(exp):
    from collections import deque
    
    if len(exp) & 1:
        return False
    stack = deque()
    for ch in exp:
        if ch == '(' or ch == '{' or ch == '[':
            stack.append(ch)
        if ch == ')' or ch == '}' or ch == ']':
            if not stack:
                return False
            top = stack.pop()
            if (top == '(' and ch != ')') or (top == '{' and ch != '}' or (top == '[' and ch != ']')):
                return False
    return not stack
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]