Submission #611868

# Submission time Handle Problem Language Result Execution time Memory
611868 2022-07-29T08:12:56 Z amunduzbaev Election (BOI18_election) C++17
82 / 100
3000 ms 40016 KB
#include "bits/stdc++.h"
using namespace std;
 
#define ar array
typedef int64_t ll;
#define her cerr<<"here"<<endl;

const int N = 5e5 + 5;
const int B = 150;
int a[N], pref[N], suff[N], mx[2][N / B + 1], in[N / B + 1][B + 1][B + 1];
int pos[N / B + 1][B + 1], sos[N / B + 1][B + 1], used[N];
int pv[N / B + 1], sv[N / B + 1];

signed main(){
	ios::sync_with_stdio(0); cin.tie(0);
	
	int n; cin >> n;
	string s; cin >> s;
	
	for(int b=0;b * B<n;b++){
		int l = b * B, r = min(n, (b + 1) * B);
		memset(pos[b], -1, sizeof pos[b]);
		for(int i=l;i<r;i++){
			if(s[i] == 'C') pref[i]--;
			else pref[i]++;
			if(i + 1 < r) pref[i + 1] = pref[i];
			mx[0][b] = max(mx[0][b], pref[i]);
			if(pref[i] > 0 && pos[b][pref[i]] == -1) pos[b][pref[i]] = i;
		}
		
		memset(sos[b], -1, sizeof sos[b]);
		for(int i=r-1;i>=l;i--){
			suff[i] = suff[i + 1];
			if(s[i] == 'C') suff[i]--;
			else suff[i]++;
			mx[1][b] = max(mx[1][b], suff[i]);
			if(suff[i] > 0 && sos[b][suff[i]] == -1) sos[b][suff[i]] = i;
		}
		mx[1][b]++, mx[0][b]++;
		for(int i=mx[0][b] - 1;i>0;i--){
			int cc = 0, r = i;
			for(int j=mx[1][b] - 1;j>0;j--){
				while(r < mx[0][b] && pos[b][r] < sos[b][j]) r++;
				if(r < mx[0][b]) cc++, r++;
				in[b][i][j] = cc;
			}
		}
	}
	
	int q; cin >> q;
	for(int i=0;i<q;i++){
		int l, r; cin >> l >> r;
		l--, r--;
		int l_ = l / B, r_ = r / B;
		if(l_ == r_){
			int sum = 0, x = 1, cnt = 0;
			for(int i=l;i<=r;i++){
				if(s[i] == 'C') sum--;
				else sum++;
				if(sum == x) used[i] = 1, cnt++, x++;
			}
			int is = 0; sum = 0, x = 1;
			for(int i=r;i>=l;i--){
				if(s[i] == 'C') sum--;
				else sum++;
				if(used[i]) is++, used[i] = 0;
				if(sum == x){
					if(!is) cnt++;
					else is--;
					x++;
				}
			}
			
			cout<<cnt<<"\n";
			for(int i=l;i<=r;i++) used[i] = 0;
			continue;
		}
		
		//~ cout<<l<<" "<<(l_ + 1) * B - 1<<" <-\n";
		int sum = 0, x = 1, cnt = 0;
		for(int i=l;i<(l_ + 1) * B;i++){
			if(s[i] == 'C') sum--;
			else sum++;
			//~ cout<<i<<" "<<sum<<" "<<x<<"\n";
			if(sum == x) used[i] = 1, cnt++, x++;
		}
		
		for(int b=l_+1;b<r_;b++){
			if(mx[0][b] > x - sum) pv[b] = x - sum;
			else pv[b] = mx[0][b];
			//~ cout<<b<<" "<<mx[0][b]<<" "<<pv[b]<<" <-\n";
			x += (mx[0][b] - pv[b]);
			cnt += (mx[0][b] - pv[b]);
			sum += suff[b * B];
		}
		for(int i=r_ * B;i<=r;i++){
			if(s[i] == 'C') sum--;
			else sum++;
			//~ cout<<i<<" "<<sum<<" "<<x<<"\n";
			if(sum == x) used[i] = 1, cnt++, x++;
		}
		//~ cout<<cnt<<" : ";
		int is = 0; sum = 0, x = 1;
		for(int i=r;i>=r_*B;i--){
			if(s[i] == 'C') sum--;
			else sum++;
			if(used[i]) is++, used[i] = 0;
			if(sum == x){
				if(!is) cnt++;
				else is--;
				x++;
			}
		}
		//~ cout<<cnt<<" : ";
		for(int b=r_-1;b>l_;b--){
			if(mx[1][b] > x - sum){
				sv[b] = x - sum;
				x += (mx[1][b] - x + sum);
			} else {
				sv[b] = mx[1][b];
			}
			
			is += in[b][pv[b]][sv[b]];
			//~ cout<<is<<" "<<mx[1][b]<<" "<<sv[b]<<"\n";
			cnt += max(0, mx[1][b] - sv[b] - is);
			is -= min(is, mx[1][b] - sv[b]);
			
			is += (mx[0][b] - pv[b] - in[b][pv[b]][sv[b]]);
			sum += suff[b * B];
		}
		//~ cout<<cnt<<" : ";
		for(int i=(l_ + 1) * B - 1;i>=l;i--){
			if(s[i] == 'C') sum--;
			else sum++;
			if(used[i]) is++, used[i] = 0;
			if(sum == x){
				if(!is) cnt++;
				else is--;
				x++;
			}
		}
		
		cout<<cnt<<"\n";
	}
}




# Verdict Execution time Memory Grader output
1 Correct 3 ms 468 KB Output is correct
2 Correct 3 ms 468 KB Output is correct
3 Correct 3 ms 340 KB Output is correct
4 Correct 3 ms 724 KB Output is correct
5 Correct 2 ms 724 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 468 KB Output is correct
2 Correct 3 ms 468 KB Output is correct
3 Correct 3 ms 340 KB Output is correct
4 Correct 3 ms 724 KB Output is correct
5 Correct 2 ms 724 KB Output is correct
6 Correct 194 ms 6216 KB Output is correct
7 Correct 373 ms 5936 KB Output is correct
8 Correct 217 ms 5944 KB Output is correct
9 Correct 111 ms 6092 KB Output is correct
10 Correct 174 ms 3292 KB Output is correct
11 Correct 224 ms 12756 KB Output is correct
12 Correct 201 ms 22616 KB Output is correct
13 Correct 214 ms 28996 KB Output is correct
14 Correct 188 ms 20344 KB Output is correct
15 Correct 118 ms 13652 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 468 KB Output is correct
2 Correct 3 ms 468 KB Output is correct
3 Correct 3 ms 340 KB Output is correct
4 Correct 3 ms 724 KB Output is correct
5 Correct 2 ms 724 KB Output is correct
6 Correct 194 ms 6216 KB Output is correct
7 Correct 373 ms 5936 KB Output is correct
8 Correct 217 ms 5944 KB Output is correct
9 Correct 111 ms 6092 KB Output is correct
10 Correct 174 ms 3292 KB Output is correct
11 Correct 224 ms 12756 KB Output is correct
12 Correct 201 ms 22616 KB Output is correct
13 Correct 214 ms 28996 KB Output is correct
14 Correct 188 ms 20344 KB Output is correct
15 Correct 118 ms 13652 KB Output is correct
16 Execution timed out 3070 ms 40016 KB Time limit exceeded
17 Halted 0 ms 0 KB -