class Solution {
public:
    int smallestRangeI(vector<int>& A, int K) {
        int minVal = INT_MAX, maxVal = INT_MIN, len = A.size();
        for(int i = 0; i < len; ++i)
        {
            minVal = min(minVal, A[i]);
            maxVal = max(maxVal, A[i]);
        }
        int maxDiff = maxVal - minVal;
        return max(0, maxDiff - 2 * K);
    }
};