return {
	compress: compress,
	naive: naive
}

function compress(grid) {
	var state = {
		data: '',
		stack: 0,
		size: 0
	};
	var color;
	var count;
	for(var i = 0; i < grid.length; i++) {
		for(var j = 0; j < grid.length; j++) {
			if(color == undefined) {
				color = grid[i][j];
			} else if(grid[i][j] != color) {
			} else if(count > 6) {
			} else {
				count++;
			}
		}
	}
	return atob(compressed);
}

function appendLength(state, n) {
	append(state, 1);
	for(var i = 0; i < 3; i++) {
		append(state, n % 2);
		n >>= 1;
	}
}

function appendColor(state, c) {
	append(state, 0);
	for(var i = 0; i < 3; i++) {
		append(state, c % 2);
		c >>= 1;
	}
}

function appendColorNaive(state, c) {
	for(var i = 0; i < 3; i++) {
		append(state, c % 2);
		c >>= 1;
	}
}

function append(state, one) {
	if(state.size > 7) {
		flush(state);
	}
	state.stack = 2*state.stack + (one ? 1 : 0);
	state.size++;
}

function flush(state) {
	state.data = state.data + String.fromCharCode(state.stack);
	state.stack = 0;
	state.size = 0;
}

function naive(grid) {
	var state = {
		data: '',
		stack: 0,
		size: 0
	};
	for(var i = 0; i < grid.length; i++) {
		for(var j = 0; j < grid.length; j++) {
			appendColorNaive(state, grid[i][j]);
		}
	}
	flush(state);
	return btoa(state.data);
}