#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pb push_back
#define mp make_pair
#define pii pair<int, int>
#define fi first
#define se second
const int MAXN = 300'001;
bool vis[MAXN];
int vx[MAXN], vy[MAXN];
vector<pair<int, int>> g[MAXN];
int ptr[MAXN];
bool del[MAXN];
int ans[MAXN];
int deg[MAXN];
bool phase_1;
bool xit;
void dfs(int cur, int col = 0) {
while(ptr[cur] < g[cur].size()) {
if(xit) {
return;
}
int nei = g[cur][ptr[cur]].fi;
int id = g[cur][ptr[cur]].se;
if(del[id]) {
ptr[cur]++;
continue;
}
del[id] = true;
ans[id] = col;
deg[cur]++;
deg[nei]++;
ptr[cur]++;
dfs(nei, 1 - col);
}
if(phase_1) {
xit = true;
}
}
void solve() {
int n; cin >> n;
vector<int> comp1, comp2;
for (int i = 1; i <= n; i++) {
cin >> vx[i] >> vy[i];
comp1.emplace_back(vx[i]);
comp2.emplace_back(vy[i]);
}
sort(comp1.begin(), comp1.end());
sort(comp2.begin(), comp2.end());
comp1.erase(unique(comp1.begin(), comp1.end()), comp1.end());
comp2.erase(unique(comp2.begin(), comp2.end()), comp2.end());
for (int i = 1; i <= n; i++) {
vx[i] = lower_bound(comp1.begin(), comp1.end(), vx[i])-comp1.begin();
vy[i] = lower_bound(comp2.begin(), comp2.end(), vy[i])-comp2.begin();
g[vx[i]].emplace_back(vy[i]+n, i);
g[vy[i]+n].emplace_back(vx[i], i);
}
phase_1 = true;
for(int i = 0; i < 2 * n; i++) {
if((g[i].size() - deg[i]) % 2 == 1) {
xit = false;
dfs(i);
}
}
phase_1 = false;
for(int i = 0; i < 2 * n; i++) {
dfs(i);
}
for (int i = 1; i <= n; i++) cout << (ans[i]?'F':'L');
cout << "\n";
}
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
// int T; cin >> T; while(T--)
solve();
}
| Subtask | Sum | Test | Verdict | Time | Memory | ||
|---|---|---|---|---|---|---|---|
| subtask1 | 0/0 | ||||||
| 1 | Accepted | 8ms | 7476 KiB | ||||
| 2 | Accepted | 96ms | 18848 KiB | ||||
| subtask2 | 5/5 | ||||||
| 3 | Accepted | 93ms | 17816 KiB | ||||
| 4 | Accepted | 104ms | 17764 KiB | ||||
| subtask3 | 7/7 | ||||||
| 5 | Accepted | 93ms | 17816 KiB | ||||
| 6 | Accepted | 104ms | 17764 KiB | ||||
| 7 | Accepted | 118ms | 18028 KiB | ||||
| 8 | Accepted | 115ms | 18592 KiB | ||||
| 9 | Accepted | 145ms | 18572 KiB | ||||
| 10 | Accepted | 150ms | 20804 KiB | ||||
| subtask4 | 0/20 | ||||||
| 11 | Wrong answer | 138ms | 20988 KiB | ||||
| 12 | Wrong answer | 155ms | 18952 KiB | ||||
| 13 | Wrong answer | 148ms | 18452 KiB | ||||
| 14 | Wrong answer | 152ms | 18340 KiB | ||||
| 15 | Wrong answer | 127ms | 18588 KiB | ||||
| 16 | Accepted | 179ms | 20908 KiB | ||||
| subtask5 | 0/13 | ||||||
| 17 | Accepted | 8ms | 7476 KiB | ||||
| 18 | Accepted | 7ms | 7476 KiB | ||||
| 19 | Accepted | 7ms | 7476 KiB | ||||
| 20 | Accepted | 8ms | 7476 KiB | ||||
| 21 | Accepted | 7ms | 7444 KiB | ||||
| 22 | Accepted | 7ms | 7480 KiB | ||||
| 23 | Accepted | 8ms | 7336 KiB | ||||
| 24 | Wrong answer | 8ms | 7476 KiB | ||||
| 25 | Wrong answer | 8ms | 7504 KiB | ||||
| 26 | Wrong answer | 7ms | 7516 KiB | ||||
| 27 | Accepted | 8ms | 7504 KiB | ||||
| 28 | Accepted | 6ms | 7508 KiB | ||||
| 29 | Accepted | 7ms | 7372 KiB | ||||
| 30 | Accepted | 7ms | 7504 KiB | ||||
| 31 | Accepted | 8ms | 7312 KiB | ||||
| 32 | Accepted | 8ms | 7476 KiB | ||||
| 33 | Accepted | 7ms | 7528 KiB | ||||
| subtask6 | 0/20 | ||||||
| 34 | Accepted | 8ms | 7476 KiB | ||||
| 35 | Accepted | 7ms | 7476 KiB | ||||
| 36 | Accepted | 7ms | 7476 KiB | ||||
| 37 | Accepted | 8ms | 7476 KiB | ||||
| 38 | Accepted | 7ms | 7444 KiB | ||||
| 39 | Accepted | 7ms | 7480 KiB | ||||
| 40 | Accepted | 8ms | 7336 KiB | ||||
| 41 | Wrong answer | 8ms | 7476 KiB | ||||
| 42 | Wrong answer | 8ms | 7504 KiB | ||||
| 43 | Wrong answer | 7ms | 7516 KiB | ||||
| 44 | Accepted | 8ms | 7504 KiB | ||||
| 45 | Accepted | 6ms | 7508 KiB | ||||
| 46 | Accepted | 7ms | 7372 KiB | ||||
| 47 | Accepted | 7ms | 7504 KiB | ||||
| 48 | Accepted | 8ms | 7312 KiB | ||||
| 49 | Accepted | 8ms | 7476 KiB | ||||
| 50 | Accepted | 7ms | 7528 KiB | ||||
| 51 | Wrong answer | 7ms | 7568 KiB | ||||
| 52 | Wrong answer | 8ms | 7616 KiB | ||||
| 53 | Wrong answer | 7ms | 7528 KiB | ||||
| 54 | Wrong answer | 8ms | 7476 KiB | ||||
| 55 | Accepted | 7ms | 7560 KiB | ||||
| 56 | Accepted | 8ms | 7604 KiB | ||||
| 57 | Accepted | 7ms | 7660 KiB | ||||
| 58 | Accepted | 8ms | 7692 KiB | ||||
| 59 | Accepted | 8ms | 7488 KiB | ||||
| 60 | Accepted | 8ms | 7476 KiB | ||||
| 61 | Accepted | 8ms | 7476 KiB | ||||
| 62 | Accepted | 8ms | 7476 KiB | ||||
| 63 | Wrong answer | 8ms | 7480 KiB | ||||
| 64 | Accepted | 8ms | 7644 KiB | ||||
| 65 | Accepted | 8ms | 7476 KiB | ||||
| subtask7 | 0/35 | ||||||
| 66 | Accepted | 8ms | 7476 KiB | ||||
| 67 | Accepted | 98ms | 18976 KiB | ||||
| 68 | Accepted | 93ms | 17816 KiB | ||||
| 69 | Accepted | 104ms | 17764 KiB | ||||
| 70 | Accepted | 118ms | 18028 KiB | ||||
| 71 | Accepted | 115ms | 18592 KiB | ||||
| 72 | Accepted | 145ms | 18572 KiB | ||||
| 73 | Accepted | 150ms | 20804 KiB | ||||
| 74 | Wrong answer | 138ms | 20988 KiB | ||||
| 75 | Wrong answer | 155ms | 18952 KiB | ||||
| 76 | Wrong answer | 148ms | 18452 KiB | ||||
| 77 | Wrong answer | 152ms | 18340 KiB | ||||
| 78 | Wrong answer | 127ms | 18588 KiB | ||||
| 79 | Accepted | 179ms | 20908 KiB | ||||
| 80 | Accepted | 7ms | 7476 KiB | ||||
| 81 | Accepted | 7ms | 7476 KiB | ||||
| 82 | Accepted | 8ms | 7476 KiB | ||||
| 83 | Accepted | 7ms | 7444 KiB | ||||
| 84 | Accepted | 7ms | 7480 KiB | ||||
| 85 | Accepted | 8ms | 7336 KiB | ||||
| 86 | Wrong answer | 8ms | 7476 KiB | ||||
| 87 | Wrong answer | 8ms | 7504 KiB | ||||
| 88 | Wrong answer | 7ms | 7516 KiB | ||||
| 89 | Accepted | 8ms | 7504 KiB | ||||
| 90 | Accepted | 6ms | 7508 KiB | ||||
| 91 | Accepted | 7ms | 7372 KiB | ||||
| 92 | Accepted | 7ms | 7504 KiB | ||||
| 93 | Accepted | 8ms | 7312 KiB | ||||
| 94 | Accepted | 8ms | 7476 KiB | ||||
| 95 | Accepted | 7ms | 7528 KiB | ||||
| 96 | Wrong answer | 7ms | 7568 KiB | ||||
| 97 | Wrong answer | 8ms | 7616 KiB | ||||
| 98 | Wrong answer | 7ms | 7528 KiB | ||||
| 99 | Wrong answer | 8ms | 7476 KiB | ||||
| 100 | Accepted | 7ms | 7560 KiB | ||||
| 101 | Accepted | 8ms | 7604 KiB | ||||
| 102 | Accepted | 7ms | 7660 KiB | ||||
| 103 | Accepted | 8ms | 7692 KiB | ||||
| 104 | Accepted | 8ms | 7488 KiB | ||||
| 105 | Accepted | 8ms | 7476 KiB | ||||
| 106 | Accepted | 8ms | 7476 KiB | ||||
| 107 | Accepted | 8ms | 7476 KiB | ||||
| 108 | Wrong answer | 8ms | 7480 KiB | ||||
| 109 | Accepted | 8ms | 7644 KiB | ||||
| 110 | Accepted | 8ms | 7476 KiB | ||||
| 111 | Accepted | 93ms | 23544 KiB | ||||
| 112 | Accepted | 90ms | 24352 KiB | ||||
| 113 | Accepted | 90ms | 24376 KiB | ||||
| 114 | Accepted | 93ms | 24476 KiB | ||||
| 115 | Accepted | 89ms | 24484 KiB | ||||
| 116 | Accepted | 97ms | 24220 KiB | ||||
| 117 | Accepted | 93ms | 23344 KiB | ||||
| 118 | Accepted | 89ms | 24008 KiB | ||||
| 119 | Wrong answer | 93ms | 23336 KiB | ||||
| 120 | Wrong answer | 101ms | 21148 KiB | ||||
| 121 | Wrong answer | 94ms | 23964 KiB | ||||