ACM学习历程—SNNUOJ 1239 Counting Star Time(树状数组 && 动态规划 && 数论)

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <set>
#include <map>
#include <vector>
#include <string>
#define LL long long

using namespace std;

const int maxM = 1005;
const int maxN = 1000005;
LL d[maxN];

int lowbit(int x)
{
    return x&(-x);
}

void add(int id, int pls)
{
    while(id <= maxN)//id最大是maxN
    {
        d[id] += pls;
        id += lowbit(id);
    }
}

LL sum(int to)
{
    LL s = 0;
    while(to > 0)
    {
        s = s + d[to];
        to -= lowbit(to);
    }
    return s;
}

int gcd(int a, int b)
{
    int r;
    while (b != 0)
    {
        r = b;
        b = a%b;
        a = r;
    }
    return a;
}

struct node
{
    int x, y;

    void create(int xx, int yy)
    {
        int t = gcd(xx, yy);
        x = xx/t;
        y = yy/t;
    }

    bool operator<(node k) const
    {
        return k.x*y < k.y*x;
    }
};

int n, a[maxM][maxM];
LL p[maxM][maxM];
map<node, int> Hash;

void init()
{
    node t;
    for (int i = 1; i < maxM; ++i)
        for (int j = 1; j < maxM; ++j)
        {
            t.create(i, j);
            Hash[t] = 233;
        }
    map<node, int>::iterator it;
    int cnt = 1;
    for (it = Hash.begin(); it != Hash.end(); ++it)
        it->second = cnt++;
}

void input()
{
    memset(d, 0, sizeof(d));
    node t;
    int to;
    scanf("%d", &n);
    for (int i = n; i >= 1; --i)
        for (int j = 1; j <= n; ++j)
            scanf("%d", &a[i][j]);
    for (int j = 1; j <= n; ++j)
    {
        for (int i = 1; i <= n; ++i)
        {
            t.create(j, i);
            to = Hash[t];
            add(to, a[i][j]);
            p[j][i] = sum(to);
        }
    }
}

void work()
{
    int m, u, v;
    scanf("%d", &m);
    for (int i = 1; i <= m; ++i)
    {
        scanf("%d%d", &u, &v);
        printf("%lld\n", p[u][v]);
    }
}

int main()
{
    //freopen("test.in", "r", stdin);
    //freopen("test.out", "w", stdout);
    init();
    int T;
    scanf("%d", &T);
    for (int times = 1; times <= T; ++times)
    {
        printf("Case #%d:\n", times);
        input();
        work();
    }
    return 0;
}