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int m[1000001];
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class Solution {
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 public:
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  vector<int> arrayChange(vector<int> &nums, vector<vector<int>> &operations) {
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    for (int i = 0; i < nums.size(); ++i) m[nums[i]] = i;
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    for (auto &op : operations) {
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      nums[m[op[0]]] = op[1];
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      m[op[1]] = m[op[0]];
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    }
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    return nums;
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  }
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};