Submission #792713

# Submission time Handle Problem Language Result Execution time Memory
792713 2023-07-25T08:13:56 Z 박상훈(#10052) Line Town (CCO23_day1problem3) C++17
0 / 25
1 ms 340 KB
#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

constexpr ll INF = 4e18;

struct Seg{
	int tree[2002000];
	int sz;

	void init(int n){
		sz = n;
		fill(tree, tree+sz*2, 0);
	}

	void update(int p, ll x){
		p += sz;
		tree[p] = x;
		for (p>>=1;p;p>>=1) tree[p] = tree[p<<1] + tree[p<<1|1];
	}

	int query(int l, int r){
		++r;
		int ret = 0;
		for (l+=sz, r+=sz;l<r;l>>=1, r>>=1){
			if (l&1) ret += tree[l++];
			if (r&1) ret += tree[--r];
		}

		return ret;
	}
}tree;

int a[500500], I[500500];
ll dp[2][500500];

int cnt2[2], col_b[500500], col_f[500500], col[500500];

int f(int s, int e, int val){
	if ((e-s)%2 == 0) return val;
	return -val;
}

int main(){
	int n;
	scanf("%d", &n);
	for (int i=1;i<=n;i++) scanf("%d", a+i);

	for (int i=1;i<=n;i++){
		if (f(i, 0, a[i]) == -abs(a[i])) col[i] = 0;
		else col[i] = 1;
	}

	for (int i=1;i<=n;i++) I[i] = i;
	sort(I+1, I+n+1, [&](int i, int j){return abs(a[i]) < abs(a[j]);});
	tree.init(n+1);

	for (int i=1,r;i<=n;i=r+1){
		r = i;
		while(r+1<=n && abs(a[I[i]]) == abs(a[I[r+1]])) r++;

		for (int t=i;t<=r;t++) tree.update(I[t], 1);

		for (int z=0;z<2;z++){
			int len = r;
			int cnt = r-i+1;
			dp[z][len] = INF;

			for (int s=0;s<2;s++){

				// init here
				vector<int> V[2];
				cnt2[0] = cnt2[1] = 0;

				for (int t=i;t<=r;t++){
					int idx = I[t];

					V[col[idx]].push_back(tree.query(1, idx));
				}


				col_f[0] = z^1;
				for (int i=1;i<=cnt;i++){
					col_f[i] = col_f[i-1] ^ 1;
					if (i<=s) cnt2[col_f[i]]++; 
				}

				col_b[len] = ((z+len-1)&1) ^ 1;
				if (len >= len-(cnt-s)+1) cnt2[col_b[len]]++;
				for (int i=len-1;i>=len-(cnt-s)+1;i--){
					col_b[i] = col_b[i+1] ^ 1;
					cnt2[col_b[i]]++;
				}

				// printf("\ni = %d, z = %d, s = %d -> cnt = (%d, %d) / sz = (%d, %d)\n", i, z, s, cnt2[0], cnt2[1], (int)V[0].size(), (int)V[1].size());

				if (cnt2[0]!=(int)V[0].size() || cnt2[1]!=(int)V[1].size()) continue;

				int cp[2] = {col_f[s+1], col_f[s+2]};
				int cq[2] = {col_b[len - (cnt-s) + 1], col_b[len - (cnt-s) + 2]};

				int pp[2] = {0, 0}, pq[2] = {0, 0};
				if (s==1) {
					pp[1] = 1;
					if (cq[0]==z) pq[0]++;
					else pq[1]++;
				}

				ll cst = 0;
				cnt2[0] = cnt2[1] = 0;
				for (int i=1;i<=s;i++){
					cst += abs(V[col_f[i]][cnt2[col_f[i]]] - i);
					cnt2[col_f[i]]++;
				} 

				for (int i=len-(cnt-s)+1;i<=len;i++){
					cst += abs(V[col_b[i]][cnt2[col_b[i]]] - i);
					cnt2[col_b[i]]++;
				}

				int nz = z ^ s;

				// printf("i = %d, z = %d, s = %d -> cst = %lld\n", i, z, s, cst);


				for (int k=s;k<=cnt;k+=2){
					dp[z][len] = min(dp[z][len], dp[nz][i-1] + cst/2);
					if (k+2 > cnt) break;

					cst -= abs(V[cq[0]][pq[0]] - (len - (cnt-k) + 1));
					cst -= abs(V[cq[1]][pq[1]] - (len - (cnt-k) + 2));

					pq[0]++, pq[1]++;

					cst += abs(V[cp[0]][pp[0]] - (k+1));
					cst += abs(V[cp[1]][pp[1]] - (k+2));

					pp[0]++, pp[1]++;
				}
			}

			// printf("%d %d -> %lld\n", i, z, dp[z][i]);
		}


		// assert(i==r);

		// // abs distinct
		// int pos = I[i];
		// for (int z=0;z<2;z++){
		// 	dp[z][i] = INF;

		// 	if (f(pos, z, a[pos]) == -abs(a[pos])) dp[z][i] = min(dp[z][i], dp[z^1][i-1] + tree.query(1, pos-1));
		// 	if (f(pos, z+i-1, a[pos]) == abs(a[pos])) dp[z][i] = min(dp[z][i], dp[z][i-1] + tree.query(pos+1, n));

		// 	if (i==1) dp[z][i] = 0;

		// 	// printf("%d %d -> %lld\n", z, i, dp[z][i]);
		// }

		// tree.update(pos, 1);
	}

	if (dp[1][n]==INF) printf("-1\n");
	else printf("%lld\n", dp[1][n]);
}

Compilation message

Main.cpp: In function 'int main()':
Main.cpp:47:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |  scanf("%d", &n);
      |  ~~~~~^~~~~~~~~~
Main.cpp:48:30: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |  for (int i=1;i<=n;i++) scanf("%d", a+i);
      |                         ~~~~~^~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Incorrect 1 ms 340 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Incorrect 1 ms 340 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Incorrect 1 ms 340 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Incorrect 1 ms 340 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Incorrect 0 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Incorrect 0 ms 340 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Incorrect 1 ms 340 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 340 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Incorrect 1 ms 340 KB Output isn't correct
5 Halted 0 ms 0 KB -