1
var generate = function (numRows) {
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  let ans = new Array(numRows);
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  for (let i = 0; i < numRows; i++) {
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    let row = new Uint32Array(i + 1).fill(1),
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      mid = i >> 1;
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    for (let j = 1; j <= mid; j++) {
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      let val = ans[i - 1][j - 1] + ans[i - 1][j];
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      (row[j] = val), (row[row.length - j - 1] = val);
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    }
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    ans[i] = row;
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  }
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  return ans;
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};