The deoxygenated blood goes to the right atrium, then pumped in the right ventricle, then it goes to pulmonary artery to the lungs, to refill some oxygen.. after that, the oxygenated blood goes to the pulmonary vein then to the left atrium, pumped in the left ventricle, then to aorta, then it spreads throughout the body. AND THE CYCLE REPEATS!

in short, the sequence of that is continuous..