线段树&树状数组模板

树状数组：

 #include <bits/stdc++.h>

 using namespace std;

 const int MAXN = 5e5 + ;

 struct binit {
     int a[MAXN], n;
     void modify(int x, int k) {
         while(x <= n) {
             a[x] += k;
             x += (x & -x);
         }
     }
     int query(int x) {
         int ans = ;
         while(x) {
             ans += a[x];
             x -= (x & -x);
         }
         return ans;
     }
 }t;

 int main () {
     ios::sync_with_stdio(false);
     int m, opt, x, y;
     cin >> t.n >> m;
     for(int i = ; i <= t.n; i++) {
         cin >> x;
         t.modify(i, x);
     }
     while(m--) {
         cin >> opt >> x >> y;
         if(opt == ) t.modify(x, y);
         else cout << t.query(y) - t.query(x-) << endl;
     }
     return ;
 }

线段树：

 #include <bits/stdc++.h>

 using namespace std;

 typedef long long ll;

 const int MAXN = 1e5+;

 ll segtree[MAXN << ], tag[MAXN << ], a[MAXN];

 void pushup(int x) {
     segtree[x] = segtree[x << ] + segtree[x <<  | ];
 }

 void pushtag(int x, int l, int r) {
     tag[x << ] += tag[x], tag[x <<  | ] += tag[x];
     int mid = (l + r) >> ;
     segtree[x << ] += tag[x] * (mid - l + );
     segtree[x <<  | ] += tag[x] * (r - mid);
     tag[x] = ;
 }

 void build(int x, int l, int r) {
     if(l < r) {
         int mid = (l + r) >> ;
         build(x << , l, mid);
         build(x <<  | , mid + , r);
         pushup(x);
     } else segtree[x] = a[l];
 }

 ll query(int x, int l, int r, int ql, int qr) {
     pushtag(x, l, r);
     if(ql <= l && r <= qr) return segtree[x];
     int mid = (l + r) >> ; ll ans = ;
     if(ql <= mid) ans += query(x << , l, mid, ql, qr);
     if(qr > mid) ans += query(x <<  | , mid + , r, ql, qr);
     return ans;
 }

 void modify(int x, int l, int r, int ql, int qr, ll k) {
     pushtag(x, l, r);
     if(ql <= l && r <= qr) {
         segtree[x] += (r - l + ) * k;
         tag[x] += k;
     } else {
         int mid = (l + r) >> ;
         if(ql <= mid) modify(x << , l, mid, ql, qr, k);
         if(qr > mid) modify(x <<  | , mid+, r, ql, qr, k);
         pushup(x);
     }
 }

 int main() {
     int n, m, opt, x, y; ll k;
     scanf("%d%d", &n, &m);
     for(int i = ; i <= n; i++)
         scanf("%lld", a + i);
     build(, , n);
     for(int i = ; i <= m; i++) {
         scanf("%d", &opt);
         if(opt == ) {
             scanf("%d%d%lld", &x, &y, &k);
             modify(, , n, x, y, k);
         } else {
             scanf("%d%d", &x, &y);
             printf("%lld\n", query(, , n, x, y));
         }
     }
     return ;
 }

线段树（动态开点）：

 #include <bits/stdc++.h>

 using namespace std;

 typedef long long ll;

 struct node {
     ll data, tag;
     node *lc, *rc;

     node () {
         data = , lc = rc = NULL;
     }

     void pushup() {
         data = ;
         if(lc) data += lc->data;
         if(rc) data += rc->data;
     }

     void pushtag(int l, int r) {
         if(!lc) lc = new node;
         if(!rc) rc = new node;
         int mid = (l + r) >> ;
         lc->data += (mid - l + ) * tag, lc->tag += tag;
         rc->data += (r - mid) * tag, rc->tag += tag;
         tag = ;
     }

 } *st = new node;

 void modify(node *cur, int l, int r, int ql, int qr, ll k) {
     cur->pushtag(l, r);
     if(ql <= l && r <= qr) {
         cur->data += (r - l + ) * k;
         cur->tag = k;
     } else {
         int mid = (l + r) >> ;
         if(ql <= mid) modify(cur->lc, l, mid, ql, qr, k);
         if(qr > mid) modify(cur->rc, mid + , r, ql, qr, k);
         cur->pushup();
     }
 }

 ll query(node *cur, int l, int r, int ql, int qr) {
     cur->pushtag(l, r);
     if(ql <= l && r <= qr) {
         return cur->data;
     }
     int mid = (l + r) >> ; ll ans = ;
     if(ql <= mid) ans += query(cur->lc, l, mid, ql, qr);
     if(qr > mid) ans += query(cur->rc, mid + , r, ql, qr);
     return ans;
 }

 int main() {
     int n, m, opt, x, y; ll z;
     cin >> n >> m;
     while(m--) {
         cin >> opt;
         if(opt == ) {
             cin >> x >> y >> z;
             modify(st, , n, x, y, z);
         } else {
             cin >> x >> y;
             cout << query(st, , n, x, y) << endl;
         }
     }
     return ;
 }