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class Solution {
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  public int sumSubseqWidths(int[] nums) {
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    int MOD = (int) 1e9 + 7;
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    Arrays.sort(nums);
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    long ans = 0;
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    long p = 1;
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    for (int i = 0; i < nums.length; i++) {
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      ans = (ans + p * nums[i] - p * nums[nums.length - 1 - i]) % MOD;
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      p = (p * 2) % MOD;
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    }
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    return (int) ans;
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  }
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}