let input = ['1,2,3,3,5'];

let print = this.print || console.log;
let gets = this.gets || ((arr, index) => () => arr[index++])(input, 0);

var a = gets(), count = a[a.length - 1];
var missing = [];
for ( var i = 1; i <= count; i++ ) {
	if (a.indexOf(i) == -1) {
		missing.push(i);
	}
}
print(missing.toString());