Daliy Algorithm (数学，堆，dfs，贪心)-- day 82

Nothing to fear

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种一棵树最好的时间是十年前，其次是现在！

那些你早出晚归付出的刻苦努力，你不想训练，当你觉的太累了但还是要咬牙坚持的时候，那就是在追逐梦想，不要在意终点有什么，要享受路途的过程，或许你不能成就梦想，但一定会有更伟大的事情随之而来。 mamba out~

2020.5.18

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人一我十，人十我百，追逐青春的梦想，怀着自信的心，永不言弃！

PAT-A1147 Heaps

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <vector>
#include <cmath>
#include <cstring>

using namespace std;
const int N = 10005;
int a[N];
int m , t;
bool Max = false , Min = false;
int preorder[N];
int cnt = 2;
void dfs(int now)
{
    int ls = now * 2;
    int rs = now * 2 + 1;
    if(now > m)return;
    if(ls <= m)
    {
        if(a[now] > a[ls])Max = 1;
        else Min = 1;
        dfs(ls);
    }
    if(rs <= m)
    {
        if(a[now] > a[rs])Max = 1;
        else Min = 1;
        dfs(rs);
    }
    preorder[cnt++] = a[now];
}
void slove()
{
    for(int i = 1;i <= m ;i ++)scanf("%d",&a[i]);
    dfs(1);
    if(Min  && Max)cout << "Not Heap" << endl;
    if(Max  &&!Min)cout << "Max Heap" << endl;
    if(!Max && Min)cout << "Min Heap" << endl;
    for(int i = 1;i <= m ;i ++)
    {
        if(i == m)printf("%d\n",preorder[i]);
        else printf("%d ",preorder[i]);
    }
    return;
}
void init()
{
    Max = 0,Min = 0;
    memset(a , 0 , sizeof a);
    memset(preorder , 0 , sizeof preorder);
    cnt = 1;
}
int main()
{
    cin >> t >> m;
    while(t--)
    {
        init();
        slove();
    }
    return 0;
}

Ternary String

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstdlib>
#include <cstring>
#include <vector>
#include <cassert>
#include <string>
#include <iomanip>
#include <cmath>
#include <ctime>
#define SIS std::ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);
#define lowbit(x) (x & -x)
#define npos string::npos
using namespace std;
typedef long long ll;
const int MAX = 0x7ffffff;
int t;

void slove()
{
    string s;
    cin >> s;
    int n = s.size();
    if(s.find('1') == npos || s.find('2') == npos || s.find('3') == npos)
    {
        cout << 0 << endl;
        return ;
    }
    int a = -1, b = -1 , c = -1 , ans = n + 1;
    for(int i = 0;i < n;i ++)
    {
        if(s[i] == '1')a = i;
        if(s[i] == '2')b = i;
        if(s[i] == '3')c = i;
        //printf("%d %d %d\n",a , b ,c);
        if(a != -1 && b != -1 && c != -1)
        {
            int x = max(max(a, b) , c);
            int y = min(min(a ,b),  c);
            ans = min(abs(y - x) + 1,ans);
        }
    }
    cout << ans << endl;
}
int main()
{
#ifdef LOCAL
    auto start_time = clock();
    cerr << setprecision(3) << fixed; // 在iomanip中
#endif
    SIS;
    cin >> t;
    while(t--)
    {
        slove();
    }
#ifdef LOCAL
    auto end_time = clock();
    cerr << "Execution time: " << (end_time - start_time) * (int)1e3 / CLOCKS_PER_SEC << " ms\n";
#endif
}

Simple Polygon Embedding

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstdlib>
#include <cstring>
#include <vector>
#include <cassert>
#include <string>
#include <iomanip>
#include <cmath>
#include <ctime>
#define SIS std::ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);
#define lowbit(x) (x & -x)
using namespace std;
typedef long long ll;
const int MAX = 0x7ffffff;
int t;
const double PA = 3.14159265358979323846;
void slove()
{
    int n;
    cin >> n;
    printf("%.9f\n", 1 / tan(PA / (2 * n)));
}
int main()
{
#ifdef LOCAL
    auto start_time = clock();
    cerr << setprecision(3) << fixed; // 在iomanip中
#endif
    SIS;
    cin >> t;
    while(t--)
    {
        slove();
    }
#ifdef LOCAL
    auto end_time = clock();
    cerr << "Execution time: " << (end_time - start_time) * (int)1e3 / CLOCKS_PER_SEC << " ms\n";
#endif
}