Submission #330639

#	Time	Username	Problem	Language	Result	Execution time	Memory
330639		mickytanawin	Miners (IOI07_miners)	C++14	100 / 100	294 ms	876 KiB

miners

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

typedef pair<char, int> pci;

const int N = 1e5;

int food[N + 1], dp[2][4][4][4][4];
char str[N + 1];
map<char, int> conv = {pci('M', 1), pci('F', 2), pci('B', 3)};
int nFood;

int mineCoal(int a, int b, int c){
    int ans = 0;
    if(a == 1 || b == 1 || c == 1){
        ++ans;
    }
    if(a == 2 || b == 2 || c == 2){
        ++ans;
    }
    if(a == 3 || b == 3 || c == 3){
        ++ans;
    }
    return ans;
}

int dpTopDown(int i, int x1, int x2, int y1, int y2){
    if(i == nFood + 1){
        return 0;
    }
    if(dp[i][x1][x2][y1][y2] > 0){
        return dp[i][x1][x2][y1][y2];
    }
    return dp[i][x1][x2][y1][y2] = max(mineCoal(x1, x2, food[i]) + dpTopDown(i + 1, food[i], x1, y1, y2), mineCoal(y1, y2, food[i]) + dpTopDown(i + 1, x1, x2, food[i], y1));
}

int main(){

    scanf("%d", &nFood);
    scanf(" %s", str);
    for(int i = 1; i <= nFood; ++i){
        food[i] = conv[str[i - 1]];
    }

    for(int i = nFood + 1; i >= 1; --i){
        for(int x1 = 0; x1 <= 3; ++x1){
            for(int x2 = 0; x2 <= 3; ++x2){
                for(int y1 = 0; y1 <= 3; ++y1){
                    for(int y2 = 0; y2 <= 3; ++y2){
                        int curr = i % 2;
                        int next = curr ^ 1;
                        if(i == nFood + 1){
                            dp[curr][x1][x2][y1][y2] = 0;
                        } else {
                            dp[curr][x1][x2][y1][y2] = max(mineCoal(x1, x2, food[i]) + dp[next][food[i]][x1][y1][y2], mineCoal(y1, y2, food[i]) + dp[next][x1][x2][food[i]][y1]);
                        }
                    }
                }
            }
        }
    }

    cout << dp[1][0][0][0][0];

    return 0;
}

Compilation message (stderr)

miners.cpp: In function 'int main()':
miners.cpp:39:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   39 |     scanf("%d", &nFood);
      |     ~~~~~^~~~~~~~~~~~~~
miners.cpp:40:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   40 |     scanf(" %s", str);
      |     ~~~~~^~~~~~~~~~~~

• Subtask 1: 9 / 9
• Subtask 2: 9 / 9
• Subtask 3: 9 / 9
• Subtask 4: 9 / 9
• Subtask 5: 9 / 9
• Subtask 6: 7 / 7
• Subtask 7: 8 / 8
• Subtask 8: 8 / 8
• Subtask 9: 8 / 8
• Subtask 10: 8 / 8
• Subtask 11: 8 / 8
• Subtask 12: 8 / 8