一日一プロ
using System; namespace atcoder { class MainClass { public static void Main (string[] args) { int s, e,sum; sum = 0; for (int i = 0; i < 3; i++) { string[] str = Console.ReadLine ().Split (' '); s = int.Parse (str [0]); e = int.Parse (str [1]); sum += s * e / 10; } Console.WriteLine ("{0}",sum); } } }