1let x = 0; 2x = 1; 3x = 2; 4x = 3; 5x = 4; 6x = 5; 7x = 6; 8x = 7; 9x = 8; 10x = 9; 11x = 10; 12x = 11; 13x = 12; 14x = 13; 15x = 14; 16x = 15; 17x = 16; 18x = 17; 19x = 18; 20module.exports = x; 21