生日問題(Birthday problem). 一個房間中要有多少人, 才會使其中至少有兩人生日(月日)相同的機率大於0.5? 此程式包含算數實驗值和亂數模擬值-birthday problem, in a set of n randomly chosen people, some pair of them will have the same birthday. By the pigeonhole principle, the probability reaches 100 when the