Submission #383926

#	Time	Username	Problem	Language	Result	Execution time	Memory
383926		nikatamliani	Examination (JOI19_examination)	C++14	100 / 100	812 ms	52380 KiB

examination

#include <bits/stdc++.h>
using namespace std;
const int N = 2e5+10;
template <typename T>
struct fenwick_tree {
    int size;
    vector<T> tree;
    T neutral;
    fenwick_tree(int n, T _neutral) {
        size = n;
        neutral = _neutral;
        tree = vector<T>(n + 1);
    }

    void update(int index, T value) {
        for(; index <= size; index += index & -index) {
            tree[index] += value;
        }
    }
    T query_prefix(int index) {
        T ans = neutral;
        for(; index; index -= index & -index) {
            ans += tree[index];
        }
        return ans; 
    }
    T query(int l, int r) {
        return query_prefix(r) - query_prefix(l - 1);
    }
};
map<int, int> compress(vector<int> &coords) {
	sort(coords.begin(), coords.end());
	map<int, int> compressed;
	for(int i = 0, current = 0; i < (int)coords.size(); ++i) {
		if(i == 0 || coords[i] != coords[i - 1]) ++current;
		compressed[coords[i]] = current;
	}
	return compressed;
}
int x[N], y[N], a[N], b[N], c[N];
int main() {
	ios::sync_with_stdio(0); cin.tie(0);
	int n, m;
	cin >> n >> m; 
	vector<vector<int>> v;
	vector<int> sorted_sums;
	for(int i = 1; i <= n; ++i) {
		cin >> x[i] >> y[i];
		sorted_sums.push_back(x[i] + y[i]);
		v.push_back({x[i], y[i]});
	}
	sort(sorted_sums.begin(), sorted_sums.end());
	sort(v.begin(), v.end());
	for(int i = 1; i <= n; ++i) {
		x[i] = v[i - 1][0];
		y[i] = v[i - 1][1];
	}
	v.clear();
	for(int i = 1; i <= m; ++i) {
		cin >> a[i] >> b[i] >> c[i];
		c[i] = max(c[i], a[i] + b[i]);
	}
	map<int, int> compressed_sum, compressed_x, compressed_y;
	//sum
	vector<int> coords(n + m); 
	for(int i = 1; i <= m; ++i) {
		coords[i - 1] = c[i];
	}
	for(int i = 1; i <= n; ++i) {
		coords[i + m - 1] = x[i] + y[i];
	}
	compressed_sum = compress(coords);
	//x
	for(int i = 1; i <= m; ++i) {
		coords[i - 1] = a[i];
	}
	for(int i = 1; i <= n; ++i) {
		coords[i + m - 1] = x[i];
	}
	compressed_x = compress(coords);
	//y
	for(int i = 1; i <= m; ++i) {
		coords[i - 1] = b[i];
	}
	for(int i = 1; i <= n; ++i) {
		coords[i + m - 1] = y[i];
	}
	compressed_y = compress(coords);
	auto sum = [](int x, int y) -> int {
		return x + y;
	};
	fenwick_tree<int> tx(N, 0);
	fenwick_tree<int> ty(N, 0);
	vector<int> ans(m+1);
	for(int i = 1; i <= m; ++i) {
		int l = 0, r = n - 1, ind = n;
		while(r >= l) {
			int middle = l + r >> 1;
			if(sorted_sums[middle] >= c[i]) {
				r = middle - 1;
				ind = middle;
			} else {
				l = middle + 1;
			}
		}
		ans[i] = n - ind;
	}
	vector<int> sums[N], queries[N];
	for(int i = 1; i <= n; ++i) {
		int val = compressed_sum[x[i] + y[i]];
		sums[val].push_back(i);
	}
	for(int i = 1; i <= m; ++i) {
		int val = compressed_sum[c[i]];
		queries[val].push_back(i);
	}
	int max_sum_val = (int)compressed_sum.size();
	for(int i = max_sum_val; i >= 1; --i) {
		for(int id : sums[i]) {
			int val_x = compressed_x[x[id]];
			int val_y = compressed_y[y[id]];
			tx.update(val_x, 1); 
			ty.update(val_y, 1);
		}
		for(int id : queries[i]) {
			int val_x = compressed_x[a[id]];
			int val_y = compressed_y[b[id]];
			ans[id] -= tx.query_prefix(val_x - 1);
			ans[id] -= ty.query_prefix(val_y - 1);
		}
	}
	for(int i = 1; i <= m; ++i) {
		cout << ans[i] << '\n';
	}
}

Compilation message (stderr)

examination.cpp: In function 'int main()':
examination.cpp:98:19: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   98 |    int middle = l + r >> 1;
      |                 ~~^~~
examination.cpp:89:7: warning: variable 'sum' set but not used [-Wunused-but-set-variable]
   89 |  auto sum = [](int x, int y) -> int {
      |       ^~~

• Subtask 1: 2 / 2
• Subtask 2: 20 / 20
• Subtask 3: 21 / 21
• Subtask 4: 57 / 57