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var minCost = function (houses, cost, m, n, target) {
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  let map = new Map();
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  function dfs(idx = 0, prevColor = -1, neighborhoods = 0) {
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    if (idx === m) return neighborhoods === target ? 0 : Infinity;
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    let key = `${idx}-${prevColor}-${neighborhoods}`;
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    if (map.has(key)) return map.get(key);
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    let color = houses[idx];
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    // If the current house is already painted
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    if (color > 0) {
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      return color !== prevColor
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        ? dfs(idx + 1, color, neighborhoods + 1)
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        : dfs(idx + 1, color, neighborhoods);
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    }
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    let minCost = Infinity;
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    for (let i = 1; i <= n; i++) {
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      let potentialCost;
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      // If color i is !== prevColor, increment the neighborhood count
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      if (i !== prevColor) potentialCost = dfs(idx + 1, i, neighborhoods + 1);
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      // Otherwise, the neighborhood simply expanded so the neighborhood count stays the same
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      else potentialCost = dfs(idx + 1, i, neighborhoods);
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      if (potentialCost === Infinity) continue;
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      minCost = Math.min(minCost, cost[idx][i - 1] + potentialCost);
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    }
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    map.set(key, minCost);
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    return minCost;
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  }
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  let minCost = dfs();
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  return minCost === Infinity ? -1 : minCost;
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};