luogu P2068 统计和

二次联通门 : luogu P2068 统计和

 

 

/*
    luogu P2068 统计和
    
    线段树
    单点修改 + 区间查询总和
    5min才写完。。。被syl完虐
    其单身 N * INF 的手速实在比不上。。 
*/
#include <cstdio>

#define Max 1000005

void read (int &now)
{
    now = 0;
    bool flag = false;
    register char word = getchar ();
    while (word < '0' || word > '9')
    {
        if (word == '-')
            flag = true;
        word = getchar ();
    }
    while (word >= '0' && word <= '9')
    {
        now = now * 10 + word - '0';
        word = getchar ();
    }
    if (flag)
        now = -now;
}


struct Segment 
{
    struct Segment_Tree
    {
        int l;
        int r;
        int Sum;
        int Mid;
    };
    
    Segment_Tree tree[Max << 2];
    
    
    void Build (int l, int r, int now)
    {
        tree[now].l = l;
        tree[now].r = r;
        if (l == r)
            return ;
        tree[now].Mid = (l + r) >> 1;
        Build (l, tree[now].Mid, now << 1);
        Build (tree[now].Mid + 1, r, now << 1 | 1);
    }
    
    void Change_single (int pos, int now, int number)
    {
        if (tree[now].l == tree[now].r)
        {
            tree[now].Sum += number;
            return ;
        }
        if (pos <= tree[now].Mid)
            Change_single (pos, now << 1, number);
        else 
            Change_single (pos, now << 1 | 1, number);
        tree[now].Sum = tree[now << 1].Sum + tree[now << 1 | 1].Sum;  
    }
    
    int Query_Section_sum (int l, int r, int now)
    {
        if (tree[now].l == l && tree[now].r == r)
            return tree[now].Sum;
        if (r <= tree[now].Mid)
            return Query_Section_sum (l, r, now << 1);
        else if (l > tree[now].Mid)
            return Query_Section_sum (l, r, now << 1 | 1);
        else
            return Query_Section_sum (l, tree[now].Mid, now << 1) + Query_Section_sum (tree[now].Mid + 1, r, now << 1 | 1);         
    }
};

Segment Tree;

int N;
int pos;

int main (int argc, char *argv[])
{
    char type[5];
    read (N);
    Tree.Build (1, N, 1);
    read (N);
    int x, y;
    while (N--)
    {
        scanf ("%s", type);
        read (x);
        read (y);
        if (type[0] == 'x')
            Tree.Change_single (x, 1, y); 
        else
            printf ("%d\n", Tree.Query_Section_sum (x, y, 1));
    } 
    return 0;
}