采用js实现轮盘赌算法

function RWS(selectionProbability) {
    var sum = 0;
    var rand = Math.random();
    for (var i = 0; i < selectionProbability.length; i++) {
        sum += selectionProbability[i];
        if (sum >= rand) {
            return i;
        }
    }
}