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程式語言 - LeetCode - C++ - 303. Range Sum Query - Immutable

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題目：


解答：

class NumArray {
private:
    vector<int> sum;

public:
    NumArray(vector<int>& nums) {
        int n = nums.size();

        sum.resize(n + 1, 0);

        for (int i = 0; i < nums.size(); ++i) {
            sum[i + 1] = sum[i] + nums[i];
        }
    }
    
    int sumRange(int left, int right) {
        return sum[right + 1] - sum[left];
    }
};

/**
 * Your NumArray object will be instantiated and called as such:
 * NumArray* obj = new NumArray(nums);
 * int param_1 = obj->sumRange(left,right);
 */