LeetCode 1622 线段树懒标记板子题(c++)

using ll=long long;
class SegmentTree{
public:
    const static int N=1e5+1,mod=1e9+7;
    vector tree,markA,markB;
    SegmentTree(){
        tree.resize(N<<2,0),markA.resize(N<<2,1),markB.resize(N<<2,0);
    }
    void update(int idx, int left, int right, int lo, int hi, int val) {
        if (left > hi || right < lo) {
            return;
        }
        if (left >= lo && right <= hi) {
            if (val > 0) {
                markB[idx] = (markB[idx] + val) % mod;
            } else {
                markA[idx] = (markA[idx] * -val) % mod;
                markB[idx] = (markB[idx] * -val) % mod;
            }
        } else {
            pushDown(idx, left, right);
            int mid = left + ((right - left) >> 1);
            update(idx << 1, left, mid, lo, hi, val);
            update(idx << 1 | 1, mid + 1, right, lo, hi, val);
        }
    }

    int query(int idx, int left, int right, int lo, int hi) {
        if (left > hi || right < lo) {
            return 0;
        }
        if (left == lo && right == hi) {
            if(markA[idx]==1 && markB[idx]==0) return (int)tree[idx];
            else return (int)(markA[idx]*tree[idx]+markB[idx])%mod;
        }
        pushDown(idx, left, right);
        int mid = left + ((right - left) >> 1);
        return query(idx << 1, left, mid, lo, hi) + query(idx << 1 | 1, mid + 1, right, lo, hi);
    }

    void pushDown(int idx, int left, int right) {
        if (left <= right && (markA[idx] > 1 || markB[idx] > 0)) {
            markA[idx << 1] = (markA[idx << 1] * markA[idx]) % mod;
            markB[idx << 1] = (markB[idx << 1] * markA[idx] + markB[idx]) % mod;

            markA[idx << 1 | 1] = (markA[idx << 1 | 1] * markA[idx]) % mod;
            markB[idx << 1 | 1] = (markB[idx << 1 | 1] * markA[idx] + markB[idx]) % mod;

            markA[idx] = 1;
            markB[idx] = 0;
        }else if(left==right&& (markA[idx] > 1 || markB[idx] > 0)){
            tree[idx]=(markA[idx]*tree[idx]+markB[idx])%mod;
            markA[idx] = 1;
            markB[idx] = 0;
        }
    }
};
class Fancy {
public:
    SegmentTree tree;
    int size,n;
    Fancy() {
        size=0,n=1e5;
    }
    void append(int val) {
        tree.update(1, 0, n - 1, size, size, val);
        size++;
    }

    void addAll(int inc) {
        tree.update(1, 0, n - 1, 0, size - 1, inc);
    }

    void multAll(int m) {
        tree.update(1, 0, n - 1, 0, size - 1, -m);
    }

    int getIndex(int idx) {
        return idx >= size ? -1 : tree.query(1, 0, n - 1, idx, idx);
    }
};