题解 | 数位之和

package main

import (
	"fmt"
	"math"
)

func main() {
	var n int
	fmt.Scan(&n)
	if n < 0 {
		n = -n
	}
	sum := 0
	for i := math.Pow10(9); i >= 1; i /= 10 {
		sum += n / int(i)
		n = n % int(i)
	}
	fmt.Print(sum)
}