function schummeln() {
	var aufloesung = document.getElementById('loesung').value;
	for (var z = 1; z <= 81; z++) {
		var cell = document.getElementById('feld' + z);
		cell.value = aufloesung[z-1];
	};
	check();
}

function check() {
	spielfeld = new Array();
	for (var z = 1; z <= 81; z++) {
		spielfeld[z]=0;
	}
	for (var z = 1; z <= 9; z++) {
		if (checkzelle(z) == true) {markzelledirekt(z,'#44ff44')} else {markzelledirekt(z,'#aaaaaa')};
	}
	for (var z = 1; z <= 9; z++) {
		if (checkzeile(z) == true) {markzeile(z,1)};
	}
	for (var z = 1; z <= 9; z++) {
		if (checkspalte(z) == true) {markspalte(z,1)};
	}

	paintspielfeld();
}

function paintspielfeld()
{
	for (var z = 1; z <= 81; z++) {
		var cell = document.getElementById('feld' + z);
		if (spielfeld[z] == 1) {cell.style.background = '#ffffdd'};
		if (spielfeld[z] == 2) {cell.style.background = '#ccffcc'};
		if (spielfeld[z] == 0) {cell.style.background = '#ffffff'};

	}
}

function markzeile(zeilennr,farbe) {
	zeilennr--;
	for (var z = 1; z <= 9; z++) {
		spielfeld[z+zeilennr*9] = spielfeld[z+zeilennr*9] + farbe;
	}
}

function markspalte(spaltennr,farbe) {
	for (var z = 0; z <= 8; z++) {
		spielfeld[spaltennr+z*9] = spielfeld[spaltennr+z*9] + farbe;
	}
}

function markzelledirekt(zellennummer,farbe) {
	var cell = document.getElementById('zelle'+zellennummer);
	cell.style.background = farbe;
}

function checkzeile(zeilennr) {
	var ziffern = new Array(9);
	zeilennr--;
	for (var z = 1; z <= 9; z++) {
		var cell = document.getElementById('feld' + (z+zeilennr*9));
		ziffern.unshift(cell.value);
	}
	return pruefe(ziffern);
}

function checkspalte(spaltennr) {
	var ziffern = new Array(9);
	for (var z = 0; z <= 8; z++) {
		var cell = document.getElementById('feld' + (spaltennr+z*9));
		ziffern.unshift(cell.value);
	}
	return pruefe(ziffern);
}

function checkzelle(zellennummer) {
	var ziffern = new Array(9);
	var start;
	var cell;
	switch (zellennummer) {
	case 1:
		start = 1;
		break;
	case 2:
		start = 4;
		break;
	case 3:
		start = 7;
		break;
	case 4:
		start = 28;
		break;
	case 5:
		start = 31;
		break;
	case 6:
		start = 34;
		break;
	case 7:
		start = 55;
		break;
	case 8:
		start = 58;
		break;
	case 9:
		start = 61;
		break;
	default:
		start = 1;
		break;
}

	cell = document.getElementById('feld' + (start+0));
	ziffern.unshift(cell.value);
	cell = document.getElementById('feld' + (start+1));
	ziffern.unshift(cell.value);
	cell = document.getElementById('feld' + (start+2));
	ziffern.unshift(cell.value);
	cell = document.getElementById('feld' + (start+9));
	ziffern.unshift(cell.value);
	cell = document.getElementById('feld' + (start+10));
	ziffern.unshift(cell.value);
	cell = document.getElementById('feld' + (start+11));
	ziffern.unshift(cell.value);
	cell = document.getElementById('feld' + (start+18));
	ziffern.unshift(cell.value);
	cell = document.getElementById('feld' + (start+19));
	ziffern.unshift(cell.value);
	cell = document.getElementById('feld' + (start+20));
	ziffern.unshift(cell.value);

	return pruefe(ziffern);
}

function pruefe(ziffernarray) {
	ziffernarray.sort();
	var ziffernkette = ziffernarray.join("");
	if (ziffernkette == "123456789"){return true;}
		else {return false;};
}