#include int main() { double p,q,s[3]={0,}; scanf ("%lf %lf",&p,&q); for (int k=0;k<2;k++){ int v = k; double r = k ? p : 1-p; for (int i=0;i<3;i++){ if (v){ s[i] += r * q; r *= (1 - q); } v = !v; } } puts(s[1]