牛客周赛 + 洛谷刷题

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#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 200010;
ll a[N], b[N];
int n, k;
ll dp[2][N];//dp[i][j]是在i界中取了j之前的最大值
int main(){
    ios::sync_with_stdio(false), cin.tie(0), cout.tie(0);
    cin >> n >> k;
    for(int i = 1; i <= n; i++)cin >> a[i];
    for(int i = 1; i <= n; i++)cin >> b[i];
    dp[0][1] = a[1];
    dp[1][1] = -1e9;
    for(int i = 2; i <= n; i++){
        dp[0][i] = dp[0][i - 1] + a[i];
        if(dp[1][i - 1] >= k)dp[0][i] = max(dp[0][i], dp[1][i - 1] - k + a[i]);
        dp[1][i] = dp[1][i - 1] + b[i];
        if(dp[0][i - 1] >= k)dp[1][i] = max(dp[1][i], dp[0][i - 1] - k + b[i]);
    }
    cout << max(dp[1][n], dp[0][n]) << endl;
    
    return 0;
}

洛谷P8787砍竹子

#include<iostream>
#include<cmath>
using namespace std;
typedef long long ll;
const int N = 200010;
ll a[N], cnt[N], ans, maxx;
int n;
int main(){
	cin >> n;
	for(int i = 1; i <= n; i++){
		cin >> a[i];
		ll lon = a[i];
		while(lon - 1){
			cnt[i]++;
			lon = floor(sqrt(lon / 2 + 1));
		}
		maxx = max(maxx, cnt[i]);
	}
	for(int i = maxx; i >= 1; i--){
		for(int j = 1; j <= n; j++){
			if(cnt[j] == i){
				if(a[j] != a[j + 1]){
					ans++;
				}
				cnt[j]--;
				a[j] = floor(sqrt(a[j] / 2 + 1));
			}
		}
	}
	cout << ans << endl;
	
	
	return 0;
}

洛谷P8786李白打酒加强版

#include<iostream>
using namespace std;
const int mod = 1e9 + 7;
int n, m, dp[105][105][105];//dp[i][j][k]代表操作i次操作j次酒量为k时的方案 

int main(){
	cin >> n >> m;
	dp[0][0][2] = 1;
	for(int i = 0; i <= n; i++){
		for(int j = 0; j <= m - 1; j++){
			for(int k = 0; k <= 100; k++){//酒量最大为100 
				if(k % 2 == 0 && i)dp[i][j][k] += dp[i - 1][j][k / 2];
				if(j)dp[i][j][k] += dp[i][j - 1][k + 1];
				dp[i][j][k] %= mod;
			}
		}
	}
	cout << dp[n][m - 1][1] % mod << endl;
	
	return 0;
}