10026 - Standard Deviation
#include <cmath> #include <cstdio> #include <iostream> using namespace std; void Slove(int n) { int s[n]; double m, variance=0.0; for (int i=0; i<n; ++i) { cin >> s[i]; m+=s[i]; } m/=n; for (int i=0; i<n; ++i) variance+=pow(s[i]-m,2); printf ( "%.8lf\n", sqrt(variance/n) ); } int main(void) { int n; while (cin >> n && n) Slove(n); return 0; }
数式通りに書くだけ。。