Luogu 3690 LCT - 模板

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Code

 

#include<cstdio>
#include<cstring>
#include<algorithm>
#define rd read()
#define ll long long
using namespace std;

const int N = 1e5 + 5;
const int mod = 51061;

int n, m;

int read() {
    int X = 0, p = 1; char c = getchar();
    for (; c > '9' || c < '0'; c = getchar())
        if (c == '-') p = -1;
    for (; c >= '0' && c <= '9'; c = getchar())
        X = X * 10 + c - '0';
    return X * p;
}

namespace LCT {
    int ch[N][2], tun[N], f[N], size[N];
    ll sum[N], val[N], tim[N], ad[N];
#define lc(x) ch[x][0]
#define rc(x) ch[x][1]
    int isroot(int x) {
        return lc(f[x]) != x && rc(f[x]) != x;
    }

    int get(int x) {
        return rc(f[x]) == x;
    }

    void up(int x) {
        sum[x] = val[x];
        size[x] = 1;
        if (lc(x)) sum[x] += sum[lc(x)], size[x] += size[lc(x)];
        if (rc(x)) sum[x] += sum[rc(x)], size[x] += size[rc(x)];
        sum[x] %= mod;
    }

    void time(int x, ll d) {
        val[x] = val[x] * d % mod;
        sum[x] = sum[x] * d % mod;
        ad[x] = ad[x] * d % mod;
        tim[x] = tim[x] * d % mod;
    }

    void add(int x, ll d) {
        sum[x] = (sum[x] + d * size[x]) % mod;
        val[x] = (val[x] + d) % mod;
        ad[x] = (ad[x] + d) % mod;
    }

    void rev(int x) {
        swap(lc(x), rc(x));
        tun[x] ^= 1;
    }

    void pushdown(int x) {
        if (tim[x] != 1) {
            if (lc(x)) time(lc(x), tim[x]);
            if (rc(x)) time(rc(x), tim[x]);
            tim[x] = 1;
        }
        if (ad[x]) {
            if (lc(x)) add(lc(x), ad[x]);
            if (rc(x)) add(rc(x), ad[x]);
            ad[x] = 0;
        }
        if (tun[x]) {
            if (lc(x)) rev(lc(x));
            if (rc(x)) rev(rc(x));
            tun[x] = 0;
        }
    }

    void pd(int x) {
        if (!isroot(x))
            pd(f[x]);
        pushdown(x);
    }

    void rotate(int x) {
        int old = f[x], oldf = f[old], son = ch[x][get(x) ^ 1];
        if (!isroot(old)) ch[oldf][get(old)] = x;
        ch[x][get(x) ^ 1] = old;
        ch[old][get(x)] = son;
        f[old] = x; f[x] = oldf; f[son] = old;
        up(old); up(x);
    }

    void splay(int x) {
        pd(x);
        for (; !isroot(x); rotate(x)) 
            if(!isroot(f[x]))
                rotate(get(f[x]) == get(x) ? f[x] : x);
    }

    void access(int x) {
        for (int y = 0; x; y = x, x = f[x])
            splay(x), ch[x][1] = y, up(x);
    }

    void mroot(int x) {
        access(x); splay(x); rev(x);
    }

    void split(int x, int y) {
        mroot(x); access(y); splay(y);
    }

    void link(int x, int y) {
        mroot(x);
        f[x] = y;
    }

    void cut(int x, int y) {
        split(x, y);
        f[x] = ch[y][0] = 0;
        up(y);
    }
}
using namespace LCT;

int main()
{
    n = rd; m = rd;
    for (int i = 1; i <= n; ++i)
        size[i] = tim[i] = val[i] = sum[i] = 1;
    for (int i = 1; i < n; ++i) {
        int u = rd, v = rd;
        link(u, v);
    }
    for (; m; m--) {
        char op[5];
        scanf("%s", op);
        if (op[0] == '+') {
            int u = rd, v = rd, d = rd;
            split(u, v);
            add(v, d);
        }
        if (op[0] == '-') {
            int u = rd, v = rd;
            cut(u, v);
            u = rd; v = rd;
            link(u, v);
        }
        if (op[0] == '*') {
            int u = rd, v = rd, d = rd;
            split(u, v);
            time(v, d);
        }
        if (op[0] == '/') {
            int u = rd, v = rd;
            split(u, v);
            printf("%lld\n", sum[v] % mod);
        }
    }
}