ZZULIOJ 1145: Problematic odometer (2), Java

ZZULIOJ 1145: Problematic odometer (2), Java

Question description

A car has an odometer that can display an integer, the number of kilometers the car has traveled. However, there is a problem with this odometer: it always changes from 3 to 5, skipping the number 4. This is true for all digits on the odometer (ones, tens, hundreds, etc.). For example, if the odometer shows 15339, after the car has traveled 1 kilometer, the odometer will show 15350.

enter

Enter an integer num, which represents the value displayed by the odometer. The length must not exceed 9 digits and must not contain the integer 4.

output

Output an integer representing the actual mileage traveled.

Sample inputCopy

150

Sample outputCopy

117

import java.io.*;

public class Main {
    
    
    public static void main(String[] args) throws IOException {
    
    
        BufferedReader bf = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        int n = Integer.parseInt(bf.readLine());
        int res = 0;
        for (int i = 0; n > 0; i++) {
    
    
            int x = n % 10;
            if (x > 4) res += (int) ((x - 1) * Math.pow(9, i));
            else res += (int) (x * Math.pow(9, i));
            n /= 10;
        }
        bw.write(res + "\n");
        bw.close();
    }
}