function Main(inp) {
    var input = inp.split("\n");
    var n = Number(input[0]);
    var t = Number(input[1].split(' ')[0]);
    var a = Number(input[1].split(' ')[1]);
    var heights = input[2].split(' ').map(function(n) { return Number(n);});
    var diff = Number.MAX_VALUE;
    var index = -1;
    heights.forEach(function (h, i) {
        var d = Math.abs(Math.pow(t - h * 0.006, 2) - Math.pow(a, 2));
        if (d < diff) {
            diff = d;
            index = i; 
        }
    });
    console.log(index + 1);
}

Main(require("fs").readFileSync("/dev/stdin", "utf8"));