Main.java

package com.company;

public class Main {

    public static void main(String[] args) {
        System.out.println(read_vi32(write_vi32(10)));
    }

    static byte[] write_vi32(int res) {
        int i = 0;
        byte[] bytes = new byte[4];
        do {
            int res1 = res & 0b01111111;
            res = res >> 7;
            bytes[i] = (byte) (res1 | (res != 0 ? 0b10000000 : 0));
            i++;
        } while (i < 4 && res != 0);
        
        return bytes;
    }

    static int read_vi32(byte[] bytes) {
        int res = 0;
        for (int i = 0; i < 4; i++) {
            byte b = bytes[i];
            if ((b & 0b10000000) != 0) {
                break;
            }
            res = (res << 7) | (b & 0b01111111);
        }
        return res;
    }
}