【BZOJ】3343: 教主的魔法

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <cmath>
using namespace std;
const int MAXN = 1000001;
int pos[MAXN], a[MAXN], b[MAXN], add[MAXN];
int n, m ,block;
void reset(int x)
{
    int i;
    int l = (x-1) * block + 1;
    int r = x * block;
    if (r > n) r = n;
    for (i = l; i <= r; i++)
    {
        b[i] = a[i];
    }
    sort(b + l, b + r + 1);
}
int find(int x, int tar)
{
    int l = (x - 1)*block + 1;
    int r = x*block;
    if (r > n) r = n;
    int mid, ret=r;
    while (l <= r)
    {
        mid = (l + r) >> 1;
        if (b[mid] >= tar) r = mid-1;
        else l = mid + 1;
    }
    return ret - l + 1;
}
void Modify(int L, int R, int tar)
{
    int i;
    if (pos[L] == pos[R]) //L ans R are in the same block
    {
        for (i = L; i <= R; i++)
        {
            a[i] += tar;
        }
    }
    else 
    {
        for (i = L; i <= pos[L] * block; i++)
            a[i] += tar;
        for (i = (pos[R ]-1) * block +1; i <= R; i++)
            a[i] += tar;
    }
    reset(pos[L]);
    reset(pos[R]);
    for (i = pos[L] + 1; i < pos[R]; i++)
        add[i] += tar;
}
int Query(int L, int R, int tar)
{
    int d = 0, i;
    if (pos[L] == pos[R])
    {
        for (i = L; i <= R; i++)
        {
            if (add[i] + a[i] >= tar)
                d++;
        }
    }
    else
    {
        for (i = L; i <= pos[L] * block; i++)
            if (a[i] + add[pos[i]] >= tar) 
                d++;
        for (i = (pos[R]-1) * block + 1; i <= R; i++)
            if (a[i] + add[pos[i]] >= tar) 
                d++;
    }
    for (i = pos[L] + 1; i < pos[R]; i++)
        d += find(i, tar-add[i]);
    return d;
}
int main(int argc, char *argv[])
{
    int i, j, x, y, z, T;
    char op;
    scanf("%d%d", &n, &T);
    block = (int)sqrt(n);
    for (i = 1; i <= n; i++)
    {
        scanf("%d", &a[i]);
        b[i] = i;
        pos[i] = (i - 1) / block + 1;
    }
    if (n%block)
        m = n / block + 1;
    else m = n / block;
    for (i = 1; i <= m; i++)
        reset(i);
    while (T--)
    {
        scanf("\n%c%d%d%d", &op, &x, &y, &z);
        if (op == ‘M‘) Modify(x, y, z);
        else printf("%d\n", Query(x, y, z));
    }
    return 0;
}