#include <iostream>

using namespace std;
	int x[105000];
	int y[100090];
int main() {int i;
	int a,b=1;int c=0,d=0;
	scanf("%d%d",&a,&b);
	for(i=1;i<=a;i=i+1){if(i%b==0){c=c+1;x[c]=i;
	}else d=d+1;y[d]=i;
	}
	int s=0,t=0;
for(i=1;i<=c;i=i+1){s=s+x[i];
	}
for(i=1;i<=d;i=i+1){t=t+y[i];
	}	
printf("%.1lf %.1lf",s/(double)c,t/(double)d);

    return 0;
}

为什么精度不对？样例的第二个数差0.1