function main(arg) {
    var tmp = arg.split("\n");
    var N = parseInt(tmp[0]);
    var T = parseInt(tmp[1].split(" ")[0]);
    var A = parseInt(tmp[1].split(" ")[1]);
    var H = tmp[2].split(" ").map(n=>parseInt(n));
    var diffs = [];
    
    for(var i=0; i<H.length; i++) {
        diffs.push(Math.abs(A - (H[i] * 0.006) ));
    }
    
    var minDiff = Math.min(...diffs);
    var answer = diffs.indexOf(minDiff);
    
    console.log(answer + 1);
}

main(require('fs').readFileSync('/dev/stdin', 'utf8'));