delete pics to save space

1.1984.cpp

@@ -0,0 +1,14 @@
+#include<cstdio>
+int n; double now,res;
+int main()
+{
+	scanf("%d",&n);
+	now=420000.0/n;
+	for(int i=1;i<=n;i++)
+	{
+		res+=now;
+		now*=(1-0.5/i);
+	}
+	printf("%.2lf\n",res);
+	return 0;
+}