java - How to add a double with a variable only using one double -

public static void main(string[] args) {     scanner in = new scanner(system.in);     system.out.println("insert value year (ez = 2014): ");      double year = in.nextdouble();     system.out.println("insert value day (ex = 12): ");      double day = in.nextdouble();     system.out.println("insert number month (ex = 3): ");      double month = in.nextdouble();     double totaldays = day;      if (month == 1) {     } else if (month == 2) {          double totaldays = (totalday + 31);     } } 

i'm trying take totaldays double , use in if statement. want add variable without using anymore doubles. how?

your code incorrectly re-declares totaldays inside conditional. re-declaring variables in inner scope not want do, though. should use same variable. use compound add-assign operator, this:

totaldays += 31;