Flash Swaps arbitrage

flashswaps.sol

function startArbitrage(
    address token0,
    address token1,
    uint amount0,
    uint amount1
) external {
    address pairAddress = IUniswapV2Factory(pancakeFactory).getPair(token0, token1);
    require(pairAddress != address(0), 'This pool does not exist');

    IUniswapV2Pair(pairAddress).swap(
        amount0,
        amount1,
        address(this),
        bytes('not empty')
    );
}