Submission #260380

#	Time	Username	Problem	Language	Result	Execution time	Memory
260380		terencehill	Arranging Shoes (IOI19_shoes)	C++14	Compilation error	0 ms	0 KiB

shoes

#include <bits/stdc++.h>
#define all(X) (X).begin(),(X).end()
#define rall(X) (X).rbegin(),(X).rend()
#define pub push_back
#define puf push_front
#define pob pop_back
#define pof pop_front
#define ff first
#define ss second
#define P 1000000007
#define in(x, a, b) (a <= x && x < b)

using namespace std;
using ll = long long;
typedef pair<int, int> ii;
typedef vector<ii> vii; 
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<vii> vvii;
const ll inf = 1000000001, INF = (ll)1e18 + 1;

int upd(vi &t, int pos, int val) {
	for(int i = pos + 1; i <= t.size(); i += (i&-i)) {
		t[i - 1] += val;
	}
}

int get(vi &t, int pos) {
	int sum = 0;
	for(int i = pos + 1; i > 0; i -= (i&-i)) {
		sum += t[i - 1];
	}
	
	return sum;
}

ll count_swaps(vi a) {
	int n = a.size();
	
	vi t(n, 0);
	for(int i = 0; i < n; i++) upd(t, i, 1);
	
	vi nxt(n);
	vvi u(n + 10, vi(2, -1));
	for(int i = n - 1; i >= 0; i--) {
		nxt[i] = u[abs(a[i])][(a[i] < 0 ? 0 : 1)];
		u[abs(a[i])][(a[i] < 0 ? 1 : 0)] = i;
	}
	
	ll ans = 0;
	for(int i = 0; i < n; i++) {
		if(nxt[i] == -1 || !(get(t, i) - get(t, i - 1))) continue;
		if(a[i] < 0) ans += get(t, nxt[i]) - get(t, i) - 1;
		else ans += get(t, nxt[i]) - get(t, i);
		upd(t, nxt[i], -1);
	}
	
	return ans;
}

int main(){
	ios_base::sync_with_stdio(false);
	int n;
	cin >> n;
	
	vi a(n);
	for(int i = 0; i < n; i++) cin >> a[i];
    
    cout << count_swaps(a) << endl;
	
	return 0;
}

Compilation message (stderr)

shoes.cpp: In function 'int upd(vi&, int, int)':
shoes.cpp:23:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = pos + 1; i <= t.size(); i += (i&-i)) {
                       ~~^~~~~~~~~~~
shoes.cpp:26:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/tmp/ccVSFMqN.o: In function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'
/tmp/ccYNhbHP.o:shoes.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status