#include "sorting.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef vector<ll> vi;
typedef pair<ll,ll> ii;
typedef vector<ii> vii;
#define rep(i,a,b) for(int i = a; i < b; i++)
#define per(i,a,b) for(int i = a; i >= b; i--)
#define inf 9223372036854775807
#define all(x) x.begin(),x.end()
#define sz(x) (ll)(x).size()
#define trav(a,x) for(auto& a : x)
int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
ll lo = -1, hi = N, mid;
while (lo+1 < hi){
mid = (lo+hi)/2;
vi last; last.assign(N,0);
rep(i,0,N) last[i] = S[i];
rep(i,0,mid){
ll t1 = last[X[i]];
ll t2 = last[Y[i]];
last[Y[i]] = t1;
last[X[i]] = t2;
}
vi inv; inv.assign(N,0);
rep(i,0,N) inv[last[i]] = i;
ll cur = 0;
rep(i,0,mid){
while (cur < N && inv[cur] == cur) cur++;
if (cur == N) break;
ll s = last[cur],ls = inv[cur];
last[ls] = s;
last[cur] = cur;
inv[cur] = cur;
inv[s] = ls;
}
if (inv[N-1] != N-1) {
lo = mid;
} else {
hi = mid;
}
}
vii swap;
vi last; last.assign(N,0);
rep(i,0,N) last[i] = S[i];
rep(i,0,hi){
ll t1 = last[X[i]];
ll t2 = last[Y[i]];
last[Y[i]] = t1;
last[X[i]] = t2;
}
vi inv; inv.assign(N,0);
rep(i,0,N) inv[last[i]] = i;
ll cur = 0;
vii swap;
rep(i,0,hi){
while (cur < N && inv[cur] == cur) cur++;
if (cur == N) break;
ll s = last[cur],ls = inv[cur];
swap.push_back(make_pair(s,cur));
last[ls] = s;
last[cur] = cur;
inv[cur] = cur;
inv[s] = ls;
}
while (sz(swap) < hi) swap.push_back(make_pair(0,0));
last.assign(N,0);
inv.assign(N,0);
rep(i,0,N) last[i] = S[i];
rep(i,0,N) inv[last[i]] = i;
rep(i,0,hi){
ll t1 = last[X[i]];
ll t2 = last[Y[i]];
last[Y[i]] = t1;
last[X[i]] = t2;
inv[t1] = Y[i];
inv[t2] = X[i];
//
P[i] = inv[swap[i].first];
Q[i] = inv[swap[i].second];
last[P[i]] = swap[i].second;
last[Q[i]] = swap[i].first;
inv[swap[i].first] = Q[i];
inv[swap[i].second] = P[i];
}
return hi;
}
Compilation message
sorting.cpp: In function 'int findSwapPairs(int, int*, int, int*, int*, int*, int*)':
sorting.cpp:58:7: error: redeclaration of 'vii swap'
vii swap;
^~~~
sorting.cpp:46:7: note: 'vii swap' previously declared here
vii swap;
^~~~
sorting.cpp:82:29: warning: conversion to 'int' from '__gnu_cxx::__alloc_traits<std::allocator<long long int> >::value_type {aka long long int}' may alter its value [-Wconversion]
P[i] = inv[swap[i].first];
^
sorting.cpp:83:30: warning: conversion to 'int' from '__gnu_cxx::__alloc_traits<std::allocator<long long int> >::value_type {aka long long int}' may alter its value [-Wconversion]
Q[i] = inv[swap[i].second];
^
sorting.cpp:89:9: warning: conversion to 'int' from 'll {aka long long int}' may alter its value [-Wconversion]
return hi;
^~
sorting.cpp:16:39: warning: unused parameter 'M' [-Wunused-parameter]
int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
^
