n = int(input())
m = int(input())
matrix = [[0]*m]*m
ml = [0]*m
ind = [0]*m
for i in range(m):
    box = list(map(int,input().split()))
    matrix[i] = box
    ml[i] = max(box)
    ind[i] = max(range(m), key=lambda i: box[i])

a = max(range(m), key=lambda i: ml[i])

s = ml[a]
b = ind[a]

for i in range(n-2):
    c = ml[b]
    s += c
    b = ind[c]
print(s)