Collect the Mangoes

Jhethalal and Babita are playing with boxes of Ratnagiri Mangoes. They have a row $A$ of $N$ boxes of Mangoes. The $i$-th box has $A_i$ mango. The boxes are given to them in the order from the first box to the $N-th$ box. If a box has an even number of Mangoes, Jhethalal grabs the box. Otherwise, Babita grabs the box. Once a box is grabbed, the number of Mangoes in it gets added to the total numb