Submission #308809

#	Time	Username	Problem	Language	Result	Execution time	Memory
308809		HynDuf	Growing Vegetable is Fun 3 (JOI19_ho_t3)	C++11	100 / 100	34 ms	3200 KiB

joi2019_ho_t3

#include <bits/stdc++.h>

#define task "V"
#define all(v) (v).begin(), (v).end()
#define rep(i, l, r) for (int i = (l); i <= (r); ++i)
#define Rep(i, r, l) for (int i = (r); i >= (l); --i)
#define DB(X) { cerr << #X << " = " << (X) << '\n'; }
#define DB1(A, _) { cerr << #A << "[" << _ << "] = " << (A[_]) << '\n'; }
#define DB2(A, _, __) { cerr << #A << "[" << _ << "][" << __ << "] = " << (A[_][__]) << '\n'; }
#define DB3(A, _, __, ___) { cerr << #A << "[" << _ << "][" << __ << "][" << ___ << "] = " << (A[_][__][___]) << '\n'; }
#define PR(A, l, r) { cerr << '\n'; rep(_, l, r) DB1(A, _); cerr << '\n';}
#define SZ(x) ((int)(x).size())
#define pb push_back
#define eb emplace_back
#define pf push_front
#define F first
#define S second
#define by(x) [](const auto& a, const auto& b) { return a.x < b.x; } // sort(arr, arr + N, by(a));
#define next ___next
#define prev ___prev
#define y1 ___y1
#define left ___left
#define right ___right
#define y0 ___y0
#define div ___div
#define j0 ___j0
#define jn ___jn

using ll = long long;
using ld = long double;
using ull = unsigned long long;
using namespace std;
typedef pair<int, int> ii;
typedef pair<ii, int> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<ll> vl;
const int N = 402, INF = 1e9;
int n, dp[2][3][N][N], pre[3][N];
string s;
map<char, int> mp;
vi pos[3];
void upd(int &x, int y) {x = min(x, y);}
int main()
{
#ifdef HynDuf
    freopen(task".in", "r", stdin);
    //freopen(task".out", "w", stdout);
#else
    ios_base::sync_with_stdio(false); cin.tie(nullptr);
    #endif
    cin >> n >> s;
    s = '0' + s;
    mp['R'] = 0;
    mp['G'] = 1;
    mp['Y'] = 2;
    pos[0].eb(0);
    pos[1].eb(0);
    pos[2].eb(0);
    rep(i, 1, n)
    {
        rep(j, 0, 2) pre[j][i] = pre[j][i - 1];
        pre[mp[s[i]]][i]++;
        pos[mp[s[i]]].eb(i);
    }
    rep(i, 0, pre[0][n]) rep(j, 0, pre[1][n]) rep(t, 0, 2) dp[0][t][i][j] = INF;
    rep(t, 0, 2) dp[0][t][0][0] = 0;
    rep(i, 1, n)
    {
        int now = i & 1, lst = now ^ 1;
        rep(i1, 0, pre[0][n]) rep(j, 0, pre[1][n]) rep(t, 0, 2) dp[now][t][i1][j] = INF;
        rep(num0, 0, min(pre[0][n], (i + 1) >> 1)) rep(num1, 0, min({pre[1][n], i - num0, (i + 1) >> 1}))
        {
            int num2 = i - num0 - num1;
            if (num2 > pre[2][n]) continue;
            if (num0)
            {
                int cost0 = max(0, pre[1][pos[0][num0]] - num1) + max(0, pre[2][pos[0][num0]] - num2);
                upd(dp[now][0][num0][num1], dp[lst][1][num0 - 1][num1] + cost0);
                upd(dp[now][0][num0][num1], dp[lst][2][num0 - 1][num1] + cost0);
                //cerr << "dp[" << i << "][0][" << num0 << "][" << num1 << "] = " << dp[now][0][num0][num1] << '\n';
            }
            if (num1)
            {
                int cost1 = max(0, pre[0][pos[1][num1]] - num0) + max(0, pre[2][pos[1][num1]] - num2);
                upd(dp[now][1][num0][num1], dp[lst][0][num0][num1 - 1] + cost1);
                upd(dp[now][1][num0][num1], dp[lst][2][num0][num1 - 1] + cost1);
                //cerr << "dp[" << i << "][1][" << num0 << "][" << num1 << "] = " << dp[now][1][num0][num1] << '\n';
            }
            if (num2)
            {
                int cost2 = max(0, pre[1][pos[2][num2]] - num1) + max(0, pre[0][pos[2][num2]] - num0);
                upd(dp[now][2][num0][num1], dp[lst][1][num0][num1] + cost2);
                upd(dp[now][2][num0][num1], dp[lst][0][num0][num1] + cost2);
                //cerr << "dp[" << i << "][2][" << num0 << "][" << num1 << "] = " << dp[now][2][num0][num1] << '\n';
            }

        }
    }
    int ans = 1e9;
    rep(j, 0, 2) ans = min(ans, dp[n & 1][j][pre[0][n]][pre[1][n]]);
    cout << (ans == 1e9 ? -1 : ans);
    return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 55 / 55
• Subtask 3: 15 / 15
• Subtask 4: 25 / 25