Submission #1249566

#	Time	Username	Problem	Language	Result	Execution time	Memory
1249566		Charizard2021	Triple Peaks (IOI25_triples)	C++20	35 / 100	1073 ms	1984 KiB

triples

#include<bits/stdc++.h>
#include "triples.h"
using namespace std;
bool check(int i, int j, int k, int Hi, int Hj, int Hk){
    vector<int> v;
    v.push_back(j - i);
    v.push_back(k - j);
    v.push_back(k - i);
    vector<int> v2;
    v2.push_back(Hi);
    v2.push_back(Hj);
    v2.push_back(Hk);
    sort(v2.begin(), v2.end());
    sort(v.begin(), v.end());
    if(v == v2){
        return true;
    }
    return false;
}
long long count_triples(vector<int> H){
    int n = (int)H.size();
    if(n <= 2000){
        long long ans = 0;
        for(int i = 0; i < n; i++){
            for(int k = i + 2; k < n; k++){
                if(H[k] != k - i && H[i] != k - i){
                    if(H[k] + H[i] == k - i){
                        int j1 = i + H[i];
                        int j2 = i + H[k];
                        if(i < j1 && j1 < k){
                            ans += check(i, j1, k, H[i], H[j1], H[k]);
                        }
                        if(i < j2 && j2 < k && j1 != j2){
                            ans += check(i, j2, k, H[i], H[j2], H[k]);
                        }
                    }
                }
                else{
                    if(H[k] == k - i){
                        int j1 = i + H[i];
                        int j2 = k - H[i];
                        if(i < j1 && j1 < k){
                            ans += check(i, j1, k, H[i], H[j1], H[k]);
                        }
                        if(i < j2 && j2 < k && j1 != j2){
                            ans += check(i, j2, k, H[i], H[j2], H[k]);
                        }
                    }
                    if(H[i] == k - i){
                        int j1 = i + H[k];
                        int j2 = k - H[k];
                        if(i < j1 && j1 < k){
                            ans += check(i, j1, k, H[i], H[j1], H[k]);
                        }
                        if(i < j2 && j2 < k && j1 != j2){
                            ans += check(i, j2, k, H[i], H[j2], H[k]);
                        }
                    }
                }
            }
        }
        return ans;
    }
    int thing = 0;
    for(int i = 0; i < n; i++){
        thing = max(thing, H[i]);
    }
    if(thing <= 10){
        long long ans = 0;
        for(int i = 0; i < n; i++){
            for(int j = i + 1; j <= min(i + 10, n - 1); j++){
                for(int k = j + 1; k <= min(i + 10, n - 1); k++){
                    vector<int> v;
                    v.push_back(j - i);
                    v.push_back(k - j);
                    v.push_back(k - i);
                    vector<int> v2;
                    v2.push_back(H[i]);
                    v2.push_back(H[j]);
                    v2.push_back(H[k]);
                    sort(v2.begin(), v2.end());
                    sort(v.begin(), v.end());
                    if(v == v2){
                        ans++;
                    }
                }
            }
        }
        return ans;
    }
    bool s4 = true;
    for(int i = 0; i < n - 1; i++){
        if(H[i] > H[i + 1]){
            s4 = false;
            break;
        }
    }
    if(s4){
        long long ans = 0;
        for(int k = 0; k < n; k++){
            int i = k - H[k];
            if(0 <= i && i < k){
                if(H[k] != k - i && H[i] != k - i){
                    if(H[k] + H[i] == k - i){
                        int j1 = i + H[i];
                        int j2 = i + H[k];
                        if(i < j1 && j1 < k){
                            ans += check(i, j1, k, H[i], H[j1], H[k]);
                        }
                        if(i < j2 && j2 < k && j1 != j2){
                            ans += check(i, j2, k, H[i], H[j2], H[k]);
                        }
                    }
                }
                else{
                    if(H[k] == k - i){
                        int j1 = i + H[i];
                        int j2 = k - H[i];
                        if(i < j1 && j1 < k){
                            ans += check(i, j1, k, H[i], H[j1], H[k]);
                        }
                        if(i < j2 && j2 < k && j1 != j2){
                            ans += check(i, j2, k, H[i], H[j2], H[k]);
                        }
                    }
                    if(H[i] == k - i){
                        int j1 = i + H[k];
                        int j2 = k - H[k];
                        if(i < j1 && j1 < k){
                            ans += check(i, j1, k, H[i], H[j1], H[k]);
                        }
                        if(i < j2 && j2 < k && j1 != j2){
                            ans += check(i, j2, k, H[i], H[j2], H[k]);
                        }
                    }
                }
            }
        }
        return ans;
    }
}

std::vector<int> construct_range(int M, int K) {
  return {1, 1, 1};
}

Compilation message (stderr)

triples.cpp: In function 'long long int count_triples(std::vector<int>)':
triples.cpp:141:1: warning: control reaches end of non-void function [-Wreturn-type]
  141 | }
      | ^

• Subtask 0: 0 / 0
• Subtask 1: 8 / 8
• Subtask 2: 6 / 6
• Subtask 3: 10 / 10
• Subtask 4: 11 / 11
• Subtask 5: 0 / 16
• Subtask 6: 0 / 19
• Subtask 7: 0 / 5
• Subtask 8: 0 / 5
• Subtask 9: 0 / 5
• Subtask 10: 0 / 5
• Subtask 11: 0 / 5
• Subtask 12: 0 / 5