#include <bits/stdc++.h>
using namespace std;
#define fastinput cin.tie(nullptr)->sync_with_stdio(false);
#define endl '\n'
#define ll long long
const ll mOd=1e9+7;
const int mAx=INT_MAX;
const int nUm=1e3+3;
vector<int>a;
int n,s;
bool srtd(vector<int>b){
for(int i=0 ; i<b.size()-1 ; i++){
if((s==1 && b[i]>=b[i+1]) || (s==2 && b[i]>b[i+1]))
return 0;
}
return 1;
}
vector<pair<int,int>>bfs(){
queue<pair<vector<int>,vector<pair<int,int>>>>q;
map<vector<int>,bool>vis;
q.push({a,{}});
vis[a]=1;
while(!q.empty()){
auto [x,y]=q.front(); q.pop();
if(srtd(x)) return y;
for(int i=0 ; i<x.size()-1 ; i++){
vector<int>v=x;
v[i]=x[i]^x[i+1];
if(!vis[v])
{
vis[v]=1;
auto z=y;
z.push_back({i,i+1});
q.push({v,z});
}
v=x;
v[i+1]=x[i]^x[i+1];
if(!vis[v])
{
vis[v]=1;
auto z=y;
z.push_back({i+1,i});
q.push({v,z});
}
}
}
return {};
}
int main()
{
fastinput;
cin>>n>>s;
for(int i=0 ; i<n ; i++){
int x; cin>>x;
a.push_back(x);
}
vector<pair<int,int>>v=bfs();
cout<<v.size()<<endl;
for(auto it:v)cout<<it.first+1<<" "<<it.second+1<<endl;
}
Compilation message
xorsort.cpp: In function 'bool srtd(std::vector<int>)':
xorsort.cpp:12:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
12 | for(int i=0 ; i<b.size()-1 ; i++){
| ~^~~~~~~~~~~
xorsort.cpp: In function 'std::vector<std::pair<int, int> > bfs()':
xorsort.cpp:26:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
26 | for(int i=0 ; i<x.size()-1 ; i++){
| ~^~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
348 KB |
Output is correct |
2 |
Execution timed out |
1103 ms |
207412 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
348 KB |
Output is correct |
2 |
Execution timed out |
1103 ms |
207412 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
28 ms |
6224 KB |
Output is correct |
2 |
Execution timed out |
1082 ms |
205572 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |