Codeforces Round #367 Div. 2 [11110]

#include <iostream>
#include <map>
#include <math.h>
using namespace std;
int main()
{
    double a, b;
    cin >> a >> b;
    int n;
    cin >> n;
    double MIN = 1e10;
    while (n--)
    {
        double x, y, v;
        cin >> x >> y >> v;
        double tmp = sqrt((a - x) * (a - x) + (b - y) * (b - y)) / v;
        if (tmp < MIN) MIN = tmp;
    }
    printf("%.10lf\n",MIN);
    return 0;
}

#include <iostream>
#include <map>
#include <math.h>
#include <algorithm>
#include <string>
using namespace std;

int x[100000];

int main()
{
    int n, q;
    cin >> n;
    for (int i = 0; i < n; i++)
        cin >> x[i];
    sort(x, x + n);
    cin >> q;
    while (q--)
    {
        int m;
        cin >> m;
        if (m < x[0])
        {
            cout << 0 << endl;
            continue;
        }
        if (m >= x[n - 1])
        {
            cout << n << endl;
            continue;
        }
        int l = 0, r = n - 1, mid;
        while (1)
        {
            mid = (l + r) >> 1;
            if (m < x[mid]) r = mid;
            else l = mid;
            if (l == r || l + 1 == r) break;
        }
        cout << l + 1 << endl;
    }
    //system("pause");
    return 0;
}

f[i][0]表示把前i个排好序且第i个不翻转的最小代价，f[i][1]表示把前i个排好序且第i个翻转的最小代价。

#include <iostream>
#include <map>
#include <math.h>
#include <algorithm>
#include <string>
using namespace std;

long long dp[110000][2];
bool cmp[110000][2][2];
long long c[110000];
string s[110000], r[110000];

int main()
{
    int n;
    cin >> n;
    for (int i = 1; i <= n; i++)
        cin >> c[i];
    for (int i = 1; i <= n; i++)
    {
        cin >> s[i];
        r[i] = s[i];
        reverse(r[i].begin(), r[i].end());
    }
    for (int i = 2; i <= n; i++)
    {
        if (s[i - 1] <= s[i]) cmp[i][0][0] = true;
        else cmp[i][0][0] = false;
        if (r[i - 1] <= s[i]) cmp[i][0][1] = true;
        else cmp[i][0][1] = false;
        if (s[i - 1] <= r[i]) cmp[i][1][0] = true;
        else cmp[i][1][0] = false;
        if (r[i - 1] <= r[i]) cmp[i][1][1] = true;
        else cmp[i][1][1] = false;
    }
    dp[1][0] = 0;
    dp[1][1] = c[1];
    for (int i = 2; i <= n; i++)
    {
        dp[i][0] = 1e15;
        if (cmp[i][0][0] && dp[i - 1][0] < dp[i][0])
            dp[i][0] = dp[i - 1][0];
        if (cmp[i][0][1] && dp[i - 1][1] < dp[i][0])
            dp[i][0] = dp[i - 1][1];
        dp[i][1] = 1e15;
        if (cmp[i][1][0] && dp[i - 1][0] + c[i] < dp[i][1])
            dp[i][1] = dp[i - 1][0] + c[i];
        if (cmp[i][1][1] && dp[i - 1][1] + c[i] < dp[i][1])
            dp[i][1] = dp[i - 1][1] + c[i];
    }
    long long ans;
    if (dp[n][0] < dp[n][1]) ans = dp[n][0];
    else ans = dp[n][1];
    if (ans == 1e15) cout << -1 << endl;
    else cout << ans << endl;
    //system("pause");
    return 0;
}

#include<bits/stdc++.h>
#include<set>
using namespace std;

multiset<int> ms;

int main()
{
    int n;
    cin >> n;
    ms.clear();
    ms.insert(0);
    while (n--)
    {
        char ch;
        int x;
        cin >> ch >> x;
        if (ch == ‘+‘) ms.insert(x);
        if (ch == ‘-‘) ms.erase(ms.find(x));
        if (ch == ‘?‘)
        {
            int ans = 0;
            for (int i = 30; i >= 0; i--)
            {
                int tmp;
                if ((x & (1 << i)) == 0)
                {
                    tmp = ans | (1 << i);
                    auto it = ms.lower_bound(tmp);
                    if (it == ms.end()) continue;
                    if ((*it) - tmp >= (1 << i)) continue;
                    if ((*it) & (1 << i)) ans |= (1 << i);
                }
                else
                {
                    auto it = ms.lower_bound(ans);
                    int debug = *it;
                    if ((*it) & (1 << i)) ans |= (1 << i);
                }
            }
            cout << (ans ^ x) << endl;
        }
    }
    return 0;
}