sum 문제 해결 알고리즘

# 정순
max_v = 0
for i (N):
	total = 0
	for j(N)
		total = arr[i][j]
	if max_v < total:
			max_value = total

# 역순
for i (N):
	total = 0
	for j(N)
		total = arr[j][i]
	if max_v < total:
			max_value = total

# 대각선
total = 0
for i (n)
	total += arr[i][i]
	if max_v < total:
			max_value = total

total = 0
for i (n):
	total += arr[i][n-1-i]
	if max_v < total:
			max_value = total