def f( m , r , n ) a = m * pow( ( 1 + r ) , n ) return a end def pow( x , y ) a = 1; y.times { |i| a = a * x } return a end m = 10000 r = 0.05 n = 2 printf( "%d円を利率%3.2fで%d年間預けた時の元利合計は%d円です\n" , m , r , n , f( m , r , n ) )