// r not bigger than 1
// x returns the smallest integer not less than i64*r
r not bigger than 1
x returns the smallest integer not less than i64*r
// r not bigger than 1 // x returns the smallest integer not less than i64 * r
func Int64MulRat(i64 int64, r *big.Rat) (x int64) {
	rr := new(big.Rat).Mul(r, new(big.Rat).SetInt64(i64))
	x, _ = RatToInt64(rr)
	return x
}
func Int64MulRat ( i64 int64 , r * big . Rat ) ( x int64 ) { rr := new ( big . Rat ) . Mul ( r , new ( big . Rat ) . SetInt64 ( i64 ) ) x , _ = RatToInt64 ( rr ) return x }
r not bigger than 1
x returns the smallest integer not less than i64*r
r not bigger than 1 x returns the smallest integer not less than i64 * r