Скажите почему выводит след. ошибку

Traceback (most recent call last):
File "main.py", line 7, in
min = mas[i][0]
IndexError: list index out of range

в таком коде:

n, k = [int(i) for i in input().split()]
mas = [[int(j) for j in input().split()] for i in range(n)]
for i in range(k):
min = mas[i][0]
for j in range(n):
if mas[i][j] < min:
min = mas[i][j]
print(min, end = ' ')

Molyaneya    3   10.04.2020 18:19    5