Can anybody make this code shorter using a loop?

Question

Just a short program that figures out what day it will be in an amount of days the user inputs. I have it starting at DAY 6 which is Saturday. Is there a way I can shorter the code using a loop?

import java.util.Scanner;

class Week{
    public static void main(String args[]){
        Scanner input = new Scanner(System.in);

        int days[] = {1,2,3,4,5,6,7,8};
        String dayNames[] = {"Monday","Tuesday","Wednesday","Thursday","Friday",
                "Saturday", "Sunday"};
        int numdays;

        System.out.println("Enter how many days from now: ");
        numdays = input.nextInt();

        numdays = (6 + numdays) % 7;

        if(numdays == 0){
            System.out.println(dayNames[6]);
        }
        else if(numdays == 1 ){
            System.out.println(dayNames[0]);
        }
        else if(numdays == 2){
            System.out.println(dayNames[1]);
        }
        else if(numdays == 3){
            System.out.println(dayNames[2]);
        }
        else if(numdays == 4){
            System.out.println(dayNames[3]);
        }
        else if(numdays == 5){
            System.out.println(dayNames[4]);
        }
        else if(numdays == 6){
            System.out.println(dayNames[5]);
        }
    }
}

`int days[] = {1,2,3,4,5,6,7,8};` When did the 8 day week start? I Hope it means 3 days of weekend.. You could have the extra day after Sunday & call it Funday. :) — Andrew Thompson, May 10 '13 at 04:59

score 3 · Answer 1 · answered May 10 '13 at 04:50

The following section:

if(numdays == 0){
    System.out.println(dayNames[6]);
}
else if(numdays == 1 ){
    System.out.println(dayNames[0]);
}
else if(numdays == 2){
    System.out.println(dayNames[1]);
}
else if(numdays == 3){
    System.out.println(dayNames[2]);
}
else if(numdays == 4){
    System.out.println(dayNames[3]);
}
else if(numdays == 5){
    System.out.println(dayNames[4]);
}
else if(numdays == 6){
    System.out.println(dayNames[5]);
}

... is trivially replaced with:

System.out.println(dayNames[(numdays + 6) % 7)]);

score 2 · Answer 2 · answered May 10 '13 at 04:49

2

Start with sunday:

String dayNames[] = {"Sunday", "Monday","Tuesday","Wednesday","Thursday","Friday",
            "Saturday"};

Replace the big if/else with:

System.out.println(dayNames[numdays]);

answered May 10 '13 at 04:49

Ankur

33,367
2
46
72

That has also the virtue of beginning the array with the first day of the week :) – Daniel Fischer May 10 '13 at 04:53

PSR · Answer 3 · 2013-05-10T04:53:27.897

1

You can use switch case instead of multiple if statements

like

switch(numdays) {
  case 1:  ....  break;
  case 2: ..... break;
.....
}

or

String dayNames[] = {"Sunday", "Monday","Tuesday","Wednesday","Thursday",
  "Friday","Saturday"};

then you can specify index directly

System.out.println(dayNames[numdays]);

edited May 10 '13 at 04:53

answered May 10 '13 at 04:48

PSR

39,804
41
111
151

score 0 · Answer 4 · answered May 10 '13 at 04:49

0

for(numdays=0;numdays<=6;numdays++){
System.out.println(dayNames[(numdays + 6) % 7)]);
}

answered May 10 '13 at 04:49

Vaibhav Jain

3,729
3
25
42

Evgeniy Dorofeev · Answer 5 · 2013-05-10T05:45:39.240

0

There's no need for a loop

String dayNames[] = { "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday",
                "Sunday" };
int i  = (5 + numdays) % 7;
System.out.println(dayNames[i]);

edited May 10 '13 at 05:45

answered May 10 '13 at 05:02

Evgeniy Dorofeev

133,369
30
199
275

Can anybody make this code shorter using a loop?

5 Answers5