Squares calculator

index.ts

type Square = {
  x: number;
  width: number;
}
const squares: Square[] = [
  {
    x: 0,
    width: 10,
  },
  {
    x: 10,
    width: 10,
  },
  {
    x: 7,
    width: 10,
  }, {
    x: 21,
    width: 10,
  }
];

const sortedSquares = squares.sort((a, b) => a.x - b.x);
function hasOverlap(a, b) {
  return a.x <= b.x + b.width && b.x <= a.x + a.width;
}
const standaloneSquares = sortedSquares.reduce((acc, square) => {
  if (acc.current === null) {
    acc.current = square;
    return acc;
  } else if (hasOverlap(acc.current, square)) {
    acc.current = {
      x: Math.min(acc.current.x, square.x),
      width: Math.max(acc.current.x + acc.current.width, square.x + square.width) - Math.min(acc.current.x, square.x),
    };
  } else {
    acc.prev.push(acc.current);
    acc.current = square;
  }
  return acc;
}, {
  prev: [],
  get all() {
    return [...this.prev, this.current];
  },
  current: null,
} as {
  prev: Square[];
  all: Square[];
  current: Square | null;
})

console.log(standaloneSquares.all);