Submission #5418215

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Source Code Expand

N, K = map(int, input().split())
WP = sorted([list(map(int, input().split())) for i in range(N)], key=lambda x: x[1], reverse=True)


def check(half):
    cur = 0
    salt = sorted(WP, key=lambda x: x[0]*(x[1]-half), reverse=True)
    for i in range(K):
        cur += salt[i][0] * (salt[i][1]-half)
    if cur >= 0:
        return True
    return False


lower = 0
upper = 100
while upper - lower > 10 ** (-5):
    half = (upper+lower) / 2
    if check(half):
        lower = half
    else:
        upper = half

print(lower)

Submission Info

Judge Result