Sometimes some mathematical results is hard to believe. One of the common problems is the birthday paradox. Suppose you is in a party where there is people including you. What's the probability that at least and the party has same birthday? Surprisingly the result is more than 0.5. Now this is the opposite. You are given the number of days in a year. Remember that's you can are in a different planet, for example, in Mars, and a year are 669 days long. You has to find the minimum number of people you has to invite in a party such that the probability of at least B peop The Le in the party has same birthday is at least 0.5.
Input
Input starts with an integer T (≤20000), denoting the number of test cases.
Each case contains an integer n (1≤n≤105) in a single line, denoting the number of days in a year in the plan Et.
Output
For each case, print the case number and the desired result.
Sample Input |
Output for Sample Input |
2 365 669 |
Case 1:22 Case 2:30 |
Find out more people to ensure that two people birthday on the same day the probability is greater than 0.5.
1#include <cstdio>2 intMain ()3 {4 intt,k=0;5scanf"%d",&t);6 while(t--)7 {8 Doublen,p=1;9scanf"%LF",&n);Ten inti; One for(i=1;; i++) A { -P*= ((n-i)/n); - if(P <=0.5) the Break; - } -printf"Case %d:%d\n",++k,i); -}
Light OJ 1104 Birthday Paradox (probability problem)