Submission #1259014

#	Time	Username	Problem	Language	Result	Execution time	Memory
1259014		SugarCubes69	Triple Peaks (IOI25_triples)	C++20	Compilation error	0 ms	0 KiB

triples

//orz Dominater069

#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;

long long count_triples(std::vector<int> h) {
    ll ans = 0;
    ll N = h.size();

    for(int i=0;i<N;i++){
        int k = h[i]+i,j;
        if(k>=N) continue;
        
        //h[j] = j-i, h[k] = k-j
        j = k-h[k];
        if(i<j && j<k && h[j]==j-i) ans++;

        //h[j] = k-j, h[k] = j-i
        j = h[k]+i;
        if(j==k-h[k]) continue;
        if(i<j && j<k && h[j]==k-j) ans++;
    }

    for(int k=0;k<N;k++){
        int i = k-h[k],j;
        if(i<0) continue;

        //h[i] = j-i, h[j] = k-j
        j = i+h[i];
        if(i<j && j<k && h[j]==k-j) ans++;

        //h[i] = k-j, h[j] = j-i
        j = k-h[i];
        if(j==i+h[i]) continue;
        if(i<j && j<k && h[j]==j-i) ans++;
    }

    for(int i=0;i<N;i++){
        //h[i] = j-i, h[j]=k-i, h[k] = k-j
        int j = h[i]+i;
        int k = h[j]+i;
        if(i<j && j<k && h[k]==k-j) ans++;
    }

    vector<ll> grp[2*N+1];
    for(int i=0;i<N;i++) grp[h[i]-i+N].push_back(i);
    for(int x=0;x<=2*N;x++){
        if(grp[x].size()*grp[x].size()<=N){
            for(int _i=0;_i<grp[x].size();_i++) for(int _j=_i+1;_j<grp[x].size();_j++){
                int i=grp[x][_i],j=grp[x][_j];
                //h[i] = k-j, h[j] = k-i h[k] = j-i
                int k = j+h[i];
                if(k>=N) continue;
                if(i<j && j<k && h[j]==k-i && h[k]==j-i){
                    ans++;
                }
            }
        }
        else{
            for(int k=0;k<N;k++){
                //k-h[k]-x == 2i
                int _x = x-N;
                int tmp = k-h[k]-_x;
                if(tmp>=0 && tmp%2==0){
                    int i = tmp/2; //h[i] = k-j
                    int j = k-h[i]; //h[j] = j-i
                    if(i<j && j<k && h[i]==k-j && h[j]==j-i){
                        ans++;
                    }
                }
            }
        }
    }

    return ans;
}
/*std::vector<int> construct_range(int M, int K) {
    vector<int> res; res.push_back(1);
    for (int i = 1; i < M; i ++) res.push_back(i);
    return res;
}


void run_part1() {
  int N;
  assert(1 == scanf("%d", &N));
  std::vector<int> H(N);
  for (int i = 0; i < N; i++)
    assert(1 == scanf("%d", &H[i]));
  fclose(stdin);

  long long T = count_triples(H);

  printf("%lld\n", T);
  fclose(stdout);
}

void run_part2() {
  int M, K;
  assert(2 == scanf("%d %d", &M, &K));
  fclose(stdin);

  std::vector<int> H = construct_range(M, K);

  int N = H.size();
  printf("%d\n", N);
  for (int i = 0; i < N; i++)
    printf("%d%c", H[i], " \n"[i + 1 == N]);
  fclose(stdout);
}


int main() {
  int part;
  assert(1 == scanf("%d", &part));
  if (part == 1)
    run_part1();
  else if (part == 2)
    run_part2();

  return 0;
}*/

Compilation message (stderr)

/usr/bin/ld: /tmp/cchnMymV.o: in function `main':
grader.cpp:(.text.startup+0x18a): undefined reference to `construct_range(int, int)'
collect2: error: ld returned 1 exit status