import java.util.*;

public class Ex15Collapse {

	public static int[] collapse(int[] list) {
		int[] list2 = new int[(list.length+1)/2];
		for (int i = 0, j = 0; i < list.length; i+=2,j++) {
			if (i + 1 < list.length) {
				list2[j] = list[i] + list[i+1];
			}
			else {
				list2[j] = list[i];
			}
		}
		return list2;
	}
	
	public static void main(String[] args) {
		int[] list1 = { 7,2,8,9,4,13,7,1,9,10 };
		int[] list2 = { 1,2,3,4,5 };
		System.out.println( Arrays.toString( collapse(list1) ) );
		System.out.println( Arrays.toString( collapse(list2) ) );
	}

}