oj.uz

Submission #61543

# Submission time Handle Problem Language Result Execution time Memory
61543 2018-07-26T07:23:59 Z koosaga(#1775) Election (BOI18_election) C++11
100 / 100
 1705 ms 88544 KB 
#include<bits/stdc++.h>
using namespace std;
using pi = pair<int, int>;
using lint = long long;
const int MAXN = 500005;
const int MAXT = 1050000;

int a[MAXN], nxt[19][MAXN], edg[19][MAXN];
char str[MAXN];
vector<pi> v;

struct seg{
	int tree[MAXT], lim;
	void init(int n, int *a){
		for(lim = 1; lim <= n; lim <<= 1);
		fill(tree, tree + MAXT, -1e9);
		for(int i=0; i<n; i++) tree[i + lim] = a[i];
		for(int i=lim-1; i; i--) tree[i] = max(tree[2*i], tree[2*i+1]);
	}
	int query(int s, int e){
		s += lim;
		e += lim;
		int ret = -1e9;
		while(s < e){
			if(s % 2 == 1) ret = max(ret, tree[s++]);
			if(e % 2 == 0) ret = max(ret, tree[e--]);
			s >>= 1;
			e >>= 1;
		}
		if(s == e) ret = max(ret, tree[s]);
		return ret;
	}
}seg;

int main(){
	int n; scanf("%d",&n);
	scanf("%s", str + 1);
	for(int i=1; i<=n; i++){
		if(str[i] == 'C') a[i] = a[i-1] + 1;
		else a[i] = a[i-1] - 1;
	}
	seg.init(n + 1, a);
	for(int i=0; i<=n; i++) v.push_back(pi(a[i], i));
	sort(v.begin(), v.end());
	for(int i=0; i<=n; i++){
		auto k = lower_bound(v.begin(), v.end(), pi(a[i] - 1, i));
		if(k == v.end() || k->first != a[i] - 1){
			nxt[0][i] = n + 1;
			edg[0][i] = -1e9;
		}
		else{
			nxt[0][i] = k->second;
			edg[0][i] = seg.query(i, nxt[0][i] - 1);
		}
	}
	nxt[0][n+1] = n+1;
	edg[0][n+1] = -1e9;
	for(int i=1; i<19; i++){
		for(int j=n+1; j>=0; j--){
			nxt[i][j] = nxt[i-1][nxt[i-1][j]];
			edg[i][j] = max(edg[i-1][j] - (1<<(i-1)), edg[i-1][nxt[i-1][j]]);
		}
	}
	int q; scanf("%d",&q);
	while(q--){
		int l, r;
		scanf("%d %d",&l,&r);
		l--;
		int dap = -1e9;
		int cnt = 0;
		for(int i=18; i>=0; i--){
			if(nxt[i][l] <= r){
				cnt += (1<<i);
				dap = max(dap - (1<<i), edg[i][l]);
				l = nxt[i][l];
			}
		}
		dap = max(dap - 1, seg.query(l, r));
		printf("%d\n", cnt + dap - a[r]);
	}
}

Compilation message

election.cpp: In function 'int main()':
election.cpp:36:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  int n; scanf("%d",&n);
         ~~~~~^~~~~~~~~
election.cpp:37:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%s", str + 1);
  ~~~~~^~~~~~~~~~~~~~~
election.cpp:64:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  int q; scanf("%d",&q);
         ~~~~~^~~~~~~~~
election.cpp:67:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d",&l,&r);
   ~~~~~^~~~~~~~~~~~~~~

Subtask #1
28.0 / 28.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 4984 KB Output is correct
2 Correct 9 ms 5220 KB Output is correct
3 Correct 9 ms 5220 KB Output is correct
4 Correct 9 ms 5220 KB Output is correct
5 Correct 9 ms 5260 KB Output is correct

Subtask #2
54.0 / 54.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 4984 KB Output is correct
2 Correct 9 ms 5220 KB Output is correct
3 Correct 9 ms 5220 KB Output is correct
4 Correct 9 ms 5220 KB Output is correct
5 Correct 9 ms 5260 KB Output is correct
6 Correct 109 ms 16568 KB Output is correct
7 Correct 97 ms 16572 KB Output is correct
8 Correct 129 ms 16728 KB Output is correct
9 Correct 126 ms 16728 KB Output is correct
10 Correct 124 ms 16728 KB Output is correct
11 Correct 142 ms 16796 KB Output is correct
12 Correct 126 ms 16796 KB Output is correct
13 Correct 141 ms 16840 KB Output is correct
14 Correct 131 ms 16840 KB Output is correct
15 Correct 111 ms 16840 KB Output is correct

Subtask #3
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 4984 KB Output is correct
2 Correct 9 ms 5220 KB Output is correct
3 Correct 9 ms 5220 KB Output is correct
4 Correct 9 ms 5220 KB Output is correct
5 Correct 9 ms 5260 KB Output is correct
6 Correct 109 ms 16568 KB Output is correct
7 Correct 97 ms 16572 KB Output is correct
8 Correct 129 ms 16728 KB Output is correct
9 Correct 126 ms 16728 KB Output is correct
10 Correct 124 ms 16728 KB Output is correct
11 Correct 142 ms 16796 KB Output is correct
12 Correct 126 ms 16796 KB Output is correct
13 Correct 141 ms 16840 KB Output is correct
14 Correct 131 ms 16840 KB Output is correct
15 Correct 111 ms 16840 KB Output is correct
16 Correct 1054 ms 87584 KB Output is correct
17 Correct 823 ms 87696 KB Output is correct
18 Correct 862 ms 87696 KB Output is correct
19 Correct 884 ms 87696 KB Output is correct
20 Correct 952 ms 87696 KB Output is correct
21 Correct 1705 ms 88464 KB Output is correct
22 Correct 1145 ms 88544 KB Output is correct
23 Correct 1330 ms 88544 KB Output is correct
24 Correct 1080 ms 88544 KB Output is correct
25 Correct 832 ms 88544 KB Output is correct