BZOJ4105 [Thu Summer Camp 2015]平方运算 【线段树】

题目链接

BZOJ4105

题解

平方操作orz,虽说应该是线段树,但是不会维护啊QAQ
小瞧一眼题解。。。
平方成环?环长\(lcm\)小于\(60\)?
果然还是打表找规律题。。。。

那就很好做了,先预处理每个数是否在环上,如果当前区间存在数不在环上,就暴力修改
如果当前区间都在环上了,就处理出环,之后每次修改只在环上走一步即可
每次修改可能会重置\(logn\)个节点的信息,由于重置一次要求出环,是\(O(60)\)的,所以修改总复杂度是\(O(60nlogn)\)的,可以接受

#include<algorithm>
#include<iostream>
#include<cstdio>
#define REP(i,n) for (int i = 1; i <= (n); i++)
#define ls (u << 1)
#define rs (u << 1 | 1)
#define res register
using namespace std;
const int maxn = 100005,maxm = 10005,INF = 1000000000;
inline int read(){
    int out = 0,flag = 1; char c = getchar();
    while (c < 48 || c > 57){if (c == '-') flag = -1; c = getchar();}
    while (c >= 48 && c <= 57){out = (out << 3) + (out << 1) + c - 48; c = getchar();}
    return out * flag;
}
int ou[20];
inline void write(int x){
    if (!x) {putchar('0'); return;}
    int tmp = 0;
    while (x) ou[++tmp] = x % 10,x /= 10;
    while (tmp) putchar(ou[tmp--] + '0');
}
int n,m,P,A[maxn],Nxt[maxn],inc[maxn];
int sum[maxn << 2],tag[maxn << 2],val[maxn << 2];
int pos[maxn << 2],siz[maxn << 2];
int cir[maxn << 2][65],L,R;
inline int gcd(int a,int b){return b ? gcd(b,a % b) : a;}
inline int lcm(int a,int b){return a / gcd(a,b) * b;}
void upd(int u){
    sum[u] = sum[ls] + sum[rs];
    val[u] = val[ls] & val[rs];
    if (val[u]){
        pos[u] = 0;
        siz[u] = lcm(siz[ls],siz[rs]);
        for (int i = pos[ls],j = pos[rs],k = 0; k < siz[u]; k++){
            cir[u][k] = cir[ls][i] + cir[rs][j];
            i = i + 1 == siz[ls] ? 0 : i + 1;
            j = j + 1 == siz[rs] ? 0 : j + 1;
        }
    }
}
void pd(int u){
    if (tag[u]){
        pos[ls] = pos[ls] + tag[u];
        pos[rs] = pos[rs] + tag[u];
        if (pos[ls] >= siz[ls]) pos[ls] %= siz[ls];
        if (pos[rs] >= siz[rs]) pos[rs] %= siz[rs];
        sum[ls] = cir[ls][pos[ls]];
        sum[rs] = cir[rs][pos[rs]];
        tag[ls] += tag[u]; tag[rs] += tag[u];
        tag[u] = 0;
    }
}
void build(int u,int l,int r){
    if (l == r){
        sum[u] = A[l];
        val[u] = inc[A[l]];
        if (val[u]){
            pos[u] = 0;
            siz[u] = 0;
            cir[u][siz[u]++] = A[l];
            for (int i = Nxt[A[l]]; i != A[l]; i = Nxt[i])
                cir[u][siz[u]++] = i;
        }
        return;
    }
    int mid = l + r >> 1;
    build(ls,l,mid);
    build(rs,mid + 1,r);
    upd(u);
}
void modify(int u,int l,int r){
    if (l == r){
        if (val[u]){
            pos[u] = (pos[u] + 1) % siz[u];
            sum[u] = cir[u][pos[u]];
        }
        else {
            sum[u] = Nxt[sum[u]];
            if (inc[sum[u]]){
                val[u] = true;
                pos[u] = 0;
                siz[u] = 0;
                cir[u][siz[u]++] = sum[u];
                for (int i = Nxt[sum[u]]; i != sum[u]; i = Nxt[i])
                    cir[u][siz[u]++] = i;
            }
        }
        return;
    }
    if (l >= L && r <= R && val[u]){
        pos[u] == siz[u] - 1 ? pos[u] = 0 : pos[u]++;
        sum[u] = cir[u][pos[u]];
        tag[u]++;
        return;
    }
    pd(u);
    int mid = l + r >> 1;
    if (mid >= L) modify(ls,l,mid);
    if (mid < R) modify(rs,mid + 1,r);
    upd(u);
}
int query(int u,int l,int r){
    if (l >= L && r <= R) return sum[u];
    pd(u);
    int mid = l + r >> 1;
    if (mid >= R) return query(ls,l,mid);
    if (mid < L) return query(rs,mid + 1,r);
    return query(ls,l,mid) + query(rs,mid + 1,r);
}
int vis[maxn],fa[maxn],now;
void dfs(int u){
    vis[u] = now;
    if (vis[Nxt[u]]){
        if (vis[Nxt[u]] != now) return;
        else {
            for (int i = u; i != Nxt[u]; i = fa[i])
                inc[i] = true;
            inc[Nxt[u]] = true;
            return;
        }
    }
    fa[Nxt[u]] = u; dfs(Nxt[u]);
}
int main(){
    n = read(); m = read(); P = read(); REP(i,n) A[i] = read();
    for (int i = 0; i < P; i++) Nxt[i] = i * i % P;
    for (int i = 0; i < P; i++)
        if (!vis[i]){now++; dfs(i);}
    build(1,1,n);
    int opt;
    while (m--){
        opt = read(); L = read(); R = read();
        if (!opt) modify(1,1,n);
        else write(query(1,1,n)),putchar('\n');
    }
    return 0;
}

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转载自www.cnblogs.com/Mychael/p/9086252.html