#include <bits/stdc++.h>
using namespace std;
const int MAX_N = 1e5;
const int MAX_M = 2e5;
int n, m, d;
int h[MAX_N], a[MAX_M], b[MAX_M];
void init( int N, int D, int H[] ) {
n = N;
d = D;
for ( int i = 0; i < n; i++ )
h[i] = H[i];
}
void curseChanges( int M, int A[], int B[] ) {
m = M;
for ( int i = 0; i < M; i++ ) {
a[i] = A[i];
b[i] = B[i];
}
}
set<int> hy, sx, sy;
int question( int x, int y, int t ) {
sx.clear();
sy.clear();
for ( int i = 0; i < t; i++ ) {
if ( b[i] == x )
swap( a[i], b[i] );
if ( a[i] == y )
swap( a[i], b[i] );
if ( a[i] == x ) {
if ( sx.find( b[i] ) == sx.end() )
sx.insert( b[i] );
else
sx.erase( b[i] );
}
if ( b[i] == y ) {
if ( sy.find( a[i] ) == sy.end() )
sy.insert( a[i] );
else
sy.erase( a[i] );
}
}
hy.clear();
for ( int i: sy )
hy.insert( h[i] );
int minDist = 1e9;
for ( int i: sx ) {
int hx = h[i];
auto p = hy.upper_bound( hx );
if ( p != hy.end() )
minDist = min( minDist, *p - hx );
if ( p != hy.begin() ) {
p--;
minDist = min( minDist, hx - *p );
}
}
return minDist;
}
