def octal_To_Decimal(n):  
    num = n; 
    dec_value = 0; 
    base = 1; 
    temp = num; 
    while (temp): 
        last_digit = temp % 10; 
        temp = int(temp / 10); 
        dec_value += last_digit*base; 
        base = base * 8; 
    return dec_value; 