Submission #54774

#	Time	Username	Problem	Language	Result	Execution time	Memory
54774		Mamnoon_Siam	Sure Bet (CEOI17_sure)	C++17	0 / 100	3 ms	492 KiB

sure

//#pragma GCC optimize("Ofast,unroll-loops,no-stack-protector")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include <bits/stdc++.h>
using namespace std;

#define debug(s) cout<< #s <<" = "<< s <<endl
#define all(v) (v).begin(), (v).end()
#define KeepUnique(v) (v).erase( unique(all(v)), v.end() )
#define MEMSET(a,val) memset(a, val, sizeof a)
#define PB push_back
#define endl '\n'
typedef long long ll;

inline int myrand(int l, int r) {
	int ret = rand(); ret <<= 15; ret ^= rand();
	if(ret < 0) ret = -ret; ret %= (r-l+1); ret += l;
	return ret;
}
template <typename F, typename S>
ostream& operator << (ostream& os, const pair< F, S>& p) {
    return os<<"(" <<p.first<<", "<<p.second<<")"; }

typedef pair<int, int> ii;
template<typename T> using min_pq =
	priority_queue<T, vector<T>, greater<T> >;

//int dx[] = {-1, +0, +1, +0};
//int dy[] = {+0, +1, +0, -1};

typedef long long ll;

ll scale = 10000;

ll read() {
	ll x, y;
	scanf("%lld.%lld", &x, &y);
	while(y * 10LL < scale) y *= 10LL;
	ll ret = x * scale + y;
	return ret;
}

const int maxn = 100010;

vector<ll> L, R, LR;
int n;

ll solve(int k) {
	ll final = 0;
	int ret = -1, lo = 0, hi = min(n, k);
	while(lo <= hi) {
		int mid = lo + hi >> 1;
		int rem = min(k - mid, n);
		if(L[mid] > R[rem]) {
			hi = mid - 1;
		} else {
			ret = mid;
			lo = mid + 1;
		}
	} assert(ret != -1);
	final = L[ret];
	ret = -1, lo = 0, hi = min(n, k);
	while(lo <= hi) {
		int mid = lo + hi >> 1;
		int rem = min(k - mid, n);
		if(R[mid] > L[rem]) {
			hi = mid - 1;
		} else {
			ret = mid;
			lo = mid + 1;
		}
	} assert(ret != -1);
	final = max(final, R[ret]);
	return final - scale * k;
}

int32_t main () {
	cin >> n;
	L.resize(n), R.resize(n);
	for(int i = 0; i < n; i++) {
		L[i] = read();
		R[i] = read();
	}
	sort(all(L)), sort(all(R));
	reverse(all(L)), reverse(all(R));
	for(int i = 1; i < n; i++) L[i] += L[i - 1], R[i] += R[i - 1];
	L.insert(L.begin(), 0); R.insert(R.begin(), 0);
	ll mx = 0;
	for(int i = 0; i <= (n << 1); i++) {
		mx = max(mx, solve(i));
	} cout << fixed << setprecision(4) << double(mx) / double(scale) << endl;
}

Compilation message (stderr)

sure.cpp: In function 'int myrand(int, int)':
sure.cpp:17:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if(ret < 0) ret = -ret; ret %= (r-l+1); ret += l;
  ^~
sure.cpp:17:26: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
  if(ret < 0) ret = -ret; ret %= (r-l+1); ret += l;
                          ^~~
sure.cpp: In function 'll solve(int)':
sure.cpp:52:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   int mid = lo + hi >> 1;
             ~~~^~~~
sure.cpp:64:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   int mid = lo + hi >> 1;
             ~~~^~~~
sure.cpp: In function 'll read()':
sure.cpp:37:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld.%lld", &x, &y);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 20
• Subtask 2: 0 / 40
• Subtask 3: 0 / 40