n, k = map(int, input().split())
s = input()
for i in range(k - 1, n):
    print(s[i], end="")
if (n - k) % 2 == 0:
    for i in range(k - 2, -1, -1):
        print(s[i], end="")
else:
    for i in range(k - 1):
        print(s[i], end="")
print()