#include "sorting.h"
#include<iostream>
#include<vector>
#include<algorithm>
#include<utility>
#include<cassert>
using namespace std;
namespace{
struct DSU{
vector<int> dsu, sz;
DSU(int n){
dsu.resize(n + 1);
sz.resize(n + 1);
for(int i = 1; i <= n; i++) dsu[i] = i, sz[i] = 1;
}
int query(int x){
if(x == dsu[x]) return x;
dsu[x] = query(dsu[x]);
return dsu[x];
}
void unite(int a, int b){
a = query(a);
b = query(b);
if(a == b) return;
if(sz[a] < sz[b]) swap(a, b);
dsu[b] = a;
sz[a] += sz[b];
}
};
}
int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
int n = N;
for(int i = 0; i < M; i++) assert(X[i] == 0 && Y[i] == 1);
vector<int> pos(n);
for(int i = 0; i < n; i++) pos[S[i]] = i;
int now = n - 1, cur;
if(n == 2){
if(S[0] == 0) return 0;
else{
P[0] = 0;
Q[0] = 0;
return 1;
}
}
for(int i = 0; i < M; i++){
swap(S[X[i]], S[Y[i]]);
swap(pos[S[X[i]]], pos[S[Y[i]]]);
if(pos[now] == now){
P[i] = now;
Q[i] = now;
}
else{
P[i] = now;
Q[i] = pos[now];
swap(S[now], S[pos[now]]);
swap(pos[S[now]], pos[S[pos[now]]]);
}
if(now == 2){
cur = i;
break;
}
now--;
}
cur++;
if(S[0] == 0){
return cur;
}
else{
P[cur] = 0;
Q[cur] = 0;
return cur + 1;
}
/*int l = 0, r = M;
while(l < r){
int mid = (l + r) >> 1;
DSU dsu(n);
vector<int> vec(n);
for(int i = 0; i < n; i++) vec[i] = S[i];
for(int i = 0; i < mid; i++) swap(vec[X[i]], vec[Y[i]]);
for(int i = 0; i < n; i++) dsu.unite(vec[i], i);
vector<bool> vis(n);
int cc = 0;
for(int i = 0; i < n; i++){
if(!vis[dsu.query(i)]){
vis[dsu.query(i)] = 1;
cc++;
}
}
if(n - cc <= mid) r = mid;
else l = mid + 1;
}
DSU dsu(n);
vector<int> pos(n);
for(int i = 0; i < l; i++) swap(S[X[i]], S[Y[i]]);
for(int i = 0; i < n; i++) dsu.unite(i, S[i]), pos[S[i]] = i;
vector<vector<int>> children(n);
for(int i = 0; i < n; i++) children[dsu.query(i)].push_back(i);
int cur = 0;
for(int i = 0; i < n; i++){
if((int)children[i].size() >= 2){
int sz = children[i].size();
for(int j = 0; j < sz - 1; j++){
int id = children[i][j];
P[cur] = id;
Q[cur] = pos[id];
swap(S[P[cur]], S[Q[cur]]);
swap(pos[S[P[cur]]], pos[S[Q[cur]]]);
cur++;
}
}
}
while(cur < l - 1){
P[cur] = 0;
Q[cur] = 0;
cur++;
}
return l;*/
}
// g++ -std=c++17 -Wall -Wextra -fsanitize=undefined -fsanitize=address -Wshadow -o run sorting.cpp grader.cpp
Compilation message
sorting.cpp: In function 'int findSwapPairs(int, int*, int, int*, int*, int*, int*)':
sorting.cpp:65:5: warning: 'cur' may be used uninitialized in this function [-Wmaybe-uninitialized]
65 | cur++;
| ~~~^~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
1 ms |
344 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
1 ms |
344 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
1 ms |
344 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
1 ms |
604 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
1 ms |
604 KB |
Execution killed with signal 6 |
2 |
Halted |
0 ms |
0 KB |
- |