[HDU 6315] Naive Operations

[题目链接]

           http://acm.hdu.edu.cn/showproblem.php?pid=6315

[算法]

         线段树

[代码]

         

#include<bits/stdc++.h>
using namespace std;
#define MAXN 100010

int i,n,q,l,r;
int b[MAXN];
char op[10];

struct SegmentTree
{
        struct Node
        {
                int l,r;
                int sum,val;
                int tag;
        } Tree[MAXN << 2];
        inline void update(int index)
        {
                Tree[index].val = min(Tree[index << 1].val,Tree[index << 1 | 1].val);
                Tree[index].sum = Tree[index << 1].sum + Tree[index << 1 | 1].sum;
        }
        inline void pushdown(int index)
        {
                if (Tree[index].tag)
                {
                        Tree[index << 1].val -= Tree[index].tag;
                        Tree[index << 1 | 1].val -= Tree[index].tag;
                        Tree[index << 1].tag += Tree[index].tag;
                        Tree[index << 1 | 1].tag += Tree[index].tag; 
                        Tree[index].tag = 0;
                }
        }
        inline void build(int index,int l,int r)
        {
                int mid;
                Tree[index].l = l;
                Tree[index].r = r;
                Tree[index].sum = 0;
                Tree[index].tag = 0;
                if (l == r) 
                {
                        Tree[index].val = b[l];
                        return;
                }
                mid = (l + r) >> 1;
                build(index << 1,l,mid);
                build(index << 1 | 1,mid + 1,r);
                update(index);
        }
        inline void modify(int index,int l,int r)
        {
                int mid;
                if (l == r)
                {
                        Tree[index].val = b[l];
                        Tree[index].sum++;
                        return;
                }
                pushdown(index);
                mid = (Tree[index].l + Tree[index].r) >> 1;
                if (!Tree[index << 1].val) modify(index << 1,l,mid);
                if (!Tree[index << 1 | 1].val) modify(index << 1 | 1,mid + 1,r);
                update(index);
        }
        inline void add(int index,int l,int r)
        {
                int mid;
                if (Tree[index].l == l && Tree[index].r == r)
                {
                        Tree[index].val--;
                        Tree[index].tag++;
                        if (Tree[index].val == 0) modify(index,l,r);
                        return;
                }
                pushdown(index);
                mid = (Tree[index].l + Tree[index].r) >> 1;
                if (mid >= r) add(index << 1,l,r);
                else if (mid + 1 <= l) add(index << 1 | 1,l,r);
                else
                {
                        add(index << 1,l,mid);
                        add(index << 1 | 1,mid + 1,r);
                }
                update(index);
        }
        inline int query(int index,int l,int r)
        {
                int mid;
                if (Tree[index].l == l && Tree[index].r == r)
                        return Tree[index].sum;
                pushdown(index);
                mid = (Tree[index].l + Tree[index].r) >> 1;
                if (mid >= r) return query(index << 1,l,r);
                else if (mid + 1 <= l) return query(index << 1 | 1,l,r);
                else return query(index << 1,l,mid) + query(index << 1 | 1,mid + 1,r);
        } 
} T;

int main() 
{
        
        while (scanf("%d%d",&n,&q) != EOF)
        {
                for (i = 1; i <= n; i++) scanf("%d",&b[i]);
                T.build(1,1,n);    
                while (q--)
                {
                        scanf("%s",&op);
                        if (strcmp(op,"add") == 0) 
                        {
                                scanf("%d%d",&l,&r);
                                T.add(1,l,r);        
                        }    else
                        {
                                scanf("%d%d",&l,&r);
                                printf("%d
",T.query(1,l,r));
                        }
                }    
        }
        
        return 0;
    
}