from sys import stdin, stdout

n = int(stdin.readline())
tests = stdin.readline().strip()

group_size = n // 10
result = 0

for group_idx in range(10):
    if all([x == "T" for x in tests[group_size * group_idx : group_size * (group_idx+1)]]):
        result += 1
stdout.write(str(result)+"\n")

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from sys import stdin, stdout

n = int(stdin.readline())
tests = stdin.readline().strip()

group_size = n // 10
result = 0

for group_idx in range(10):
    if all([x == "T" for x in tests[group_size * group_idx : group_size * (group_idx+1)]]):
        result += 1
stdout.write(str(result)+"\n")