P4514 上帝造题的七分钟——二维树状数组

#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
const int maxn=2050;
int b[maxn][maxn],bi[maxn][maxn],bj[maxn][maxn],bij[maxn][maxn];
char s[2];
int n,m,num;

void add(int x,int y,int z) {for(int i=x;i<=n;i+=i&(-i)) for(int j=y;j<=m;j+=j&(-j)) b[i][j]+=z;}
void addi(int x,int y,int z) {for(int i=x;i<=n;i+=i&(-i)) for(int j=y;j<=m;j+=j&(-j)) bi[i][j]+=z;}
void addj(int x,int y,int z) {for(int i=x;i<=n;i+=i&(-i)) for(int j=y;j<=m;j+=j&(-j)) bj[i][j]+=z;}
void addij(int x,int y,int z) {for(int i=x;i<=n;i+=i&(-i)) for(int j=y;j<=m;j+=j&(-j)) bij[i][j]+=z;}



int query_(int x,int y) { int ans=0; for(int i=x;i;i-=i&(-i)) for(int j=y;j;j-=j&(-j)) ans+=b[i][j]; return ans;}
int query_i(int x,int y) { int ans=0; for(int i=x;i;i-=i&(-i)) for(int j=y;j;j-=j&(-j)) ans+=bi[i][j]; return ans;}
int query_j(int x,int y) { int ans=0; for(int i=x;i;i-=i&(-i)) for(int j=y;j;j-=j&(-j)) ans+=bj[i][j]; return ans;}
int query_ij(int x,int y) { int ans=0; for(int i=x;i;i-=i&(-i)) for(int j=y;j;j-=j&(-j)) ans+=bij[i][j]; return ans;}



void add_all(int x,int y,int num)
{
    add(x,y,num);
    addi(x,y,num*x);
    addj(x,y,num*y);
    addij(x,y,num*x*y);
}

int query(int x,int y)
{
    int ans=0;
    ans+=query_(x,y)*(x*y+x+y+1)-query_i(x,y)*(y+1)-query_j(x,y)*(x+1)+query_ij(x,y);
    return ans;
}

int main()
{
    scanf("%s%d%d",s,&n,&m);
    while(~scanf("%s",s))
    {
        int x1,y1,x2,y2;
        scanf("%d%d%d%d",&x1,&y1,&x2,&y2);
        if(s[0]==‘L‘)
        {
            scanf("%d",&num);
            add_all(x1,y1,num);
            add_all(x1,y2+1,-num);
            add_all(x2+1,y1,-num);
            add_all(x2+1,y2+1,num);
        }
        else 
        {
            printf("%d\n",query(x2,y2)-query(x2,y1-1)-query(x1-1,y2)+query(x1-1,y1-1));
        }
        
    }
    
    
    return 0;
}

struct node
{
    int tree[2050][2050];

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

    void add(int x,int y,int num)
    {
        for(int i=x; i<=n; i+=lowbit(i))
            for(int j=y; j<=m; j+=lowbit(j))
                tree[i][j]+=num;
    }

    int query(int x,int y)
    {
        int res=0;
        for(int i=x; i>=1; i-=lowbit(i))
            for(int j=y; j>=1; j-=lowbit(j))
                res+=tree[i][j];
        return res;
    }
}b,bi,bj,bij;