Codeforces-697C Lorenzo Von Matterhorn

Barney lives in NYC. NYC has infinite number of intersections numbered with positive integers starting from 1. There exists a bidirectional road between intersections i and 2i and another road between i and 2i + 1 for every positive integer i. You can clearly see that there exists a unique shortest path between any two intersections.

Initially anyone can pass any road for free. But since SlapsGiving is ahead of us, there will q consecutive events happen soon. There are two types of events:

1. Government makes a new rule. A rule can be denoted by integers vu and w. As the result of this action, the passing fee of all roads on the shortest path from u to v increases by w dollars.

2. Barney starts moving from some intersection v and goes to intersection u where there's a girl he wants to cuddle (using his fake name Lorenzo Von Matterhorn). He always uses the shortest path (visiting minimum number of intersections or roads) between two intersections.

Government needs your calculations. For each time Barney goes to cuddle a girl, you need to tell the government how much money he should pay (sum of passing fee of all roads he passes).

Input

The first line of input contains a single integer q (1 ≤ q ≤ 1 000).

The next q lines contain the information about the events in chronological order. Each event is described in form 1 v u w if it's an event when government makes a new rule about increasing the passing fee of all roads on the shortest path from u to v by w dollars, or in form 2 v u if it's an event when Barnie goes to cuddle from the intersection v to the intersection u.

1 ≤ v, u ≤ 1018, v ≠ u, 1 ≤ w ≤ 109 states for every description line.

Output

For each event of second type print the sum of passing fee of all roads Barney passes in this event, in one line. Print the answers in chronological order of corresponding events.

Example
input
7
1 3 4 30
1 4 1 2
1 3 6 8
2 4 3
1 6 1 40
2 3 7
2 2 4
output
94
0
32
Note

In the example testcase:

Here are the intersections used:

  1. Intersections on the path are 312 and 4.
  2. Intersections on the path are 42 and 1.
  3. Intersections on the path are only 3 and 6.
  4. Intersections on the path are 421 and 3. Passing fee of roads on the path are 3232 and 30 in order. So answer equals to32 + 32 + 30 = 94.
  5. Intersections on the path are 63 and 1.
  6. Intersections on the path are 3 and 7. Passing fee of the road between them is 0.
  7. Intersections on the path are 2 and 4. Passing fee of the road between them is 32 (increased by 30 in the first event and by 2 in the second).


题目大意:先给出q次操作,当输入1的时候,表示一棵完全二叉树的两个节点u、v之间最短路径的权值全部加上w,当输入2的时候,表示询问这棵树的u到v节点间最短路径的权值之和。
解题思路:其实没什么特别的。。。我一开始想的是 最近公共祖先+哈希+搜索,其实没那么麻烦,就map暴力搞就行0.0
代码:
#include <map>
#include <cstdio>
#include <vector>
#include <cstring>
using namespace std;
typedef long long LL;
map<LL, LL> m;
LL solve(LL u, LL v, LL w){
	vector<LL> vec;
	vec.clear();

	LL t = u, flag = 1;
	while(t){
		vec.push_back(t);
		t /= 2;
	}
	int len = vec.size();
	t = v;
	while(t){
		for(int i = 0; i < len; ++i){
			if(t == vec[i]) {flag = 0; break;}
		}
		if(!flag) break;
		t /= 2; 
	}

	if(w == -1){
		LL ans = 0;
		while(u != t){
			ans += m[u];
			u /= 2;
		}
		while(v != t){
			ans += m[v];
			v /= 2;
		}
		return ans;
	}else{
		while(u != t){
			m[u] += w;
			u /= 2;
		}
		while(v != t){
			m[v] += w;
			v /= 2;
		}
	}
	return 1LL;
}
int main()
{
	// freopen("test.in", "r+", stdin);
	// freopen("test.out", "w+", stdout);
	m.clear();
	LL q, op, u, v, w;
	scanf("%I64d", &q);
	while(q--){
		scanf("%I64d", &op);
		if(op == 1){
			scanf("%I64d%I64d%I64d", &u, &v, &w);

			solve(u, v, w);
		}else{
			scanf("%I64d%I64d", &u, &v);
			LL ans = solve(u, v, -1);
			printf("%I64d\n", ans);
		}
	}
	return 0;
}

不过讲道理,,,我看我的代码写的实在是搓,看到一个毛子写的代码如下:
#include <iostream>
#include <map>

using namespace std;

map<long long, long long> mp;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int q;
    cin >> q;
    for(int qq = 0; qq < q; qq++) {
        int t;
        cin >> t;
        if(t == 1) {
            long long v, u, w;
            cin >> v >> u >> w;
            while(v != u) {
                if(v < u)
                    swap(v, u);
                mp[v] += w;
                v /= 2;
            }
        }
        else {
            long long v, u;
            cin >> v >> u;
            long long ans = 0;
            while(v != u) {
                if(v < u)
                    swap(v, u);
                ans += mp[v];
                v /= 2;
            }
            cout << ans << '\n';
        }
    }
    return 0;
}

感觉还要继续努力啊。代码能力和思维能力还要继续提高~~

引用\[1\]中提到了一种树形动态规划的方法来解决CodeForces - 982C问题。在这个问题中,subtree指的是子连通块,而不是子树。为了使cnt_white - cnt_black尽可能大,可以使用两次树形动态规划来求解。第一次是自底向上的过程,维护一个dp数组,表示以每个节点为根的子树中的最大连通块。第二次是自顶向下的过程,处理自底向上过程中无法包含的树链所代表的子树。在第二次遍历中,需要维护一个sum变量,用于存储树链所代表的子树的贡献。根据ans\[u\]的正负,决定是否能对相邻的子节点做出贡献。如果ans\[u\]为正,则减去dp\[v\]就是树链所代表的子树的权值。最终,ans\[u\]代表包含节点u在内的子连通块的最大权值。\[1\] 问题: CodeForces - 982C 树形DP是什么问题?如何解决? 回答: CodeForces - 982C是一个树形动态规划问题。在这个问题中,需要求解子连通块的最大权值和,使得cnt_white - cnt_black尽可能大。解决这个问题的方法是使用两次树形动态规划。第一次是自底向上的过程,维护一个dp数组,表示以每个节点为根的子树中的最大连通块。第二次是自顶向下的过程,处理自底向上过程中无法包含的树链所代表的子树。在第二次遍历中,需要维护一个sum变量,用于存储树链所代表的子树的贡献。根据ans\[u\]的正负,决定是否能对相邻的子节点做出贡献。最终,ans\[u\]代表包含节点u在内的子连通块的最大权值。\[1\] #### 引用[.reference_title] - *1* *2* [CodeForces - 1324F Maximum White Subtree(树形dp)](https://blog.youkuaiyun.com/qq_45458915/article/details/104831678)[target="_blank" data-report-click={"spm":"1018.2226.3001.9630","extra":{"utm_source":"vip_chatgpt_common_search_pc_result","utm_medium":"distribute.pc_search_result.none-task-cask-2~all~insert_cask~default-1-null.142^v91^koosearch_v1,239^v3^insert_chatgpt"}} ] [.reference_item] [ .reference_list ]
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