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loop, with break and continue
this example from a Well House Consultants training course
Source code: Glenda.java Module: J050
public class Glenda {
/* A for loop repeats a block of code, given a starting action, a test to be made each time around, and a stepping action between each time around - usuaully, that's setting a starting value, stepping up one at a time, until a top value. ((A while loop offers more flexibility, but with more statements needed in your Java)) You can go back to the top of a loop and move on to the next iteration with "continue" and you can get out of a loop with no further action from it using a "break". You'll often want to use a variable to build up results during the running of a loop in exactly the same way that you would keep a mental note of the total so far as you added up a column of numbers by hand (does anyone still do that?). You can see that done in this example with the variables "healthmonths" which is counting the number of non-zero inputs, and "nveggies" which is maintaining a running total. It's conventional to use a variable to build up the total, then the same variable within the following code to calculate with the final result - there's no need to copy it from one variable to another. */ public static void main (String [] args) { int nveggies = 0; int healthymonths = 0; for (int month=1; month<=12; month++) { System.out.print("Month "); System.out.print(month); System.out.print(": How many carrots? "); int roots = (int) WellHouseInput.readNumber(); if (roots < 0) break; // negative no; exit loop if (roots == 0) { System.out.println("UNHEALTHY!"); continue; // go back to start of loop // (but move on to next incr) } nveggies += roots; healthymonths ++; } System.out.print("You have eaten "); System.out.print(nveggies); System.out.println(" carrots this year"); System.out.print("Healthy month count: "); System.out.println(healthymonths); } } /* ------------- Sample Output Dorothy-2:java grahamellis$ java Glenda Month 1: How many carrots? 4 Month 2: How many carrots? 5 Month 3: How many carrots? 4 Month 4: How many carrots? 0 UNHEALTHY! Month 5: How many carrots? 0 UNHEALTHY! Month 6: How many carrots? 4 Month 7: How many carrots? 3 Month 8: How many carrots? -1 You have eaten 20 carrots this year Healthy month count: 5 Dorothy-2:java grahamellis$ */ Learn about this subject
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