Submission #161160

#	Time	Username	Problem	Language	Result	Execution time	Memory
161160		pr3pony	Growing Vegetable is Fun 3 (JOI19_ho_t3)	C++14	100 / 100	154 ms	4344 KiB

joi2019_ho_t3

#include<bits/stdc++.h>
using namespace std;
template<class T>
bool cmin(T & a,T b) {return b < a ? a = b, 1 : 0;}
const int N = 405;
char s[N];
int n;
int dp[2][N][N][3];
vector<int> d[3];
int pr[N][3];
int f(int i,array<int,3> a)
{
    int s = 0;
    for (int j = 0; j < 3; ++j)
        s += max(0, pr[i][j] - a[j]);
    return s - 1;
}
int main()
{
    cin >> n >> (s + 1);
    d[0] = d[1] = d[2] = {0};
    for (int i = 1; i <= n; ++i) {
        for (int j = 0; j < 3; ++j) {
            pr[i][j] += pr[i-1][j];
            if ("RGY"[j] == s[i]) {
                d[j].push_back(i);
                pr[i][j]++;
            }
        }
    }
    int na=d[0].size()-1,nb=d[1].size()-1,nc=d[2].size()-1;
    memset(dp,0x3f,sizeof dp);
    memset(dp[0][0][0],0,3 * sizeof(int));
    array<int,3> a = {0,0,0}, b;
    int & i = a[0], & j = a[1], & k = a[2];
    int & x = b[0], & y = b[1], & z = b[2];
    for (int sa = 0; sa < n; ++sa) {
        memset(dp[(sa+1)%2],0x3f,sizeof dp[0]);
        for (i = 0; i <= min(na, sa); ++i) {
            for (j = 0; j <= min(nb, sa - i); ++j) {
                k = sa - i - j;
                if (k < 0 || k > nc)
                   continue; 
                b = a;
                for (int c = 0; c < 3; ++c) 
                    for (int u = 0; u < 3; ++u) 
                        if (u != c && b[u] + 1 < d[u].size()) {
                            b[u]++;
                            cmin(dp[(sa+1)%2][y][z][u], dp[sa%2][j][k][c] + f(d[u][b[u]],a));
                            b[u]--;
                        }
            }
        }
    }
    int ans = *min_element(dp[n%2][nb][nc],dp[n%2][nb][nc] + 3);
    if (ans == 0x3f3f3f3f)
        ans = -1;
    cout << ans << endl;

}

Compilation message (stderr)

joi2019_ho_t3.cpp: In function 'int main()':
joi2019_ho_t3.cpp:47:48: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                         if (u != c && b[u] + 1 < d[u].size()) {
joi2019_ho_t3.cpp:36:11: warning: unused variable 'x' [-Wunused-variable]
     int & x = b[0], & y = b[1], & z = b[2];
           ^

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