bzoj 2120: 数颜色

来源：互联网发布：二手域名交易平台编辑：程序博客网时间：2024/05/21 06:17
莫队水过
每次修改之间的询问用莫队搞一下，还挺快……
#include <cstdio>#include <cstring>#include <cmath>#include <algorithm>#include <map>using namespace std;#define MAXN 100003#define MAXQ 100003int n, a[MAXN], sqrtn;struct Qtype{    int num;    char opt;    int x, y;} qy[MAXQ];bool cmp(const Qtype &a, const Qtype &b){    int ax = a.x / sqrtn, bx = b.x / sqrtn;    if (ax != bx)        return ax < bx;    return a.y < b.y;}map<int, int> lisan;int lct = 0;int ct[MAXN], ans[MAXN];void work(int ql, int qr){    int l, r, m;    l = r = m = 0;    memset(ct, 0, sizeof(ct));    for (int i = ql; i < qr; ++i)        qy[i].num = i - ql;    sort(qy + ql, qy + qr, cmp);    for (int i = ql; i < qr; ++i)    {        while (l < qy[i].x)        {            if (--ct[a[l]] == 0)                --m;            ++l;        }        while (l > qy[i].x)        {            --l;            if (++ct[a[l]] == 1)                ++m;        }        while (r < qy[i].y)        {            if (++ct[a[r]] == 1)                ++m;            ++r;        }        while (r > qy[i].y)        {            --r;            if (--ct[a[r]] == 0)                --m;        }        ans[qy[i].num] = m;    }    for (int i = ql; i < qr; ++i)        printf("%d\n", ans[i - ql]);}int main(){    int Q;    scanf("%d%d", &n, &Q);    sqrtn = sqrt(n);    for (int i = 0; i < n; ++i)        scanf("%d", &a[i]);    for (int i = 0; i < Q; ++i)    {        scanf(" %c%d%d", &qy[i].opt, &qy[i].x, &qy[i].y);        --qy[i].x;    }    for (int i = 0; i < n; ++i)    {        map<int, int>::iterator it = lisan.find(a[i]);        if (it == lisan.end())        {            lisan[a[i]] = lct;            a[i] = lct++;        }        else            a[i] = it->second;    }    for (int i = 0; i < Q; ++i)        if (qy[i].opt == 'R')        {            map<int, int>::iterator it = lisan.find(qy[i].y);            if (it == lisan.end())            {                lisan[qy[i].y] = lct;                qy[i].y = lct++;            }            else                qy[i].y = it->second;        }    int last = 0;    for (int i = 0; i <= Q; ++i)        if (i == Q)            work(last, i);        else if (qy[i].opt == 'R')        {            work(last, i);            a[qy[i].x] = qy[i].y;            last = i + 1;        }    return 0;}
0 0