Pls help me

Debugging Help
#1

I am trying to solve Connecting Two Barns(USACO) but I can’t figure out what is wrong with my code :
#include <bits/stdc++.h>
using namespace std;

/*
ID: 10002181
LANG: C++
TASK: ariprog
*/

using str = string; // yay python!
using ld = long double; // or double, if TL is tight
using ll = long long;
using int64 = ll;
using db = double;
using ull = unsigned long long;

#define ch() getchar()
#define pc(x) putchar(x)
#define tcT template<class T
#define tcTU tcT, class U
tcT> using V = vector;
tcT, size_t SZ> using AR = array<T,SZ>;
using vi = V;
using vb = V;
using vpi = V<pair<int,int>>;
using vvi = V;
using vl = V;
using vd = V;
using vstr = V;

#define mp make_pair
#define pi pair <int, int>
#define all(x) begin(x), end(x)
#define sor(x) sort(all(x))
#define rev(x) reverse(all(x))
#define sz(x) (int)(x).size()
#define AR array

#define F0R(i, a, b) for (int i=a; i<b;++i)
#define FOR(i, a) for (int i=0; i<a;++i)
#define FORn(i, a) for (int i=1; i<=a;++i)
#define ROF(i,a) for(int i=a-1; i >= 0;–i)
#define R0F(i,a,b) for(int i=a; i > b;–i)
#define ROFn(i,a) for(int i=a; i > 0;–i)
#define trav(i,x) for(auto& i:x)

// pairs
#define mp make_pair
#define f first
#define s second

// vectors
#define lb lower_bound
#define ub upper_bound
#define SUM(v) accumulate(all(v), 0LL)
#define MN(v) *min_element(all(v))
#define MX(v) *max_element(all(v))
#define eb emplace_back
#define ft front()
#define bk back()
#define ins insert
#define pf push_front
#define pb push_back
#define emt empty()
#define rsz resize

#define pob pop_back()
#define pof pop_front()

#define swp(a,b) a^=b^=a^=b

#define ts to_string

#define setIO() ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)

const ll MOD = 1e9+7;
const ll MAX = 100000000000;
const ll INF = 1e18; // not too close to LLONG_MAX
const ld PI = acos((ld)-1);

#ifdef _DEBUG
freopen(“input.txt”, “r”, stdin);
freopen(“output.txt”, “w”, stdout);
#endif

const int dx[4] = {1,0,-1,0}, dy[4] = {0,1,0,-1}; // for every grid problem!!

//INPUT
#define tcTUU tcT, class …U
tcT> void re(complex& c);
tcTU> void re(pair<T,U>& p);
tcT> void re(V& v);
tcT, size_t SZ> void re(AR<T,SZ>& a);

tcT> void re(T& x) { cin >> x; }
void re(db& d) { str t; re(t); d = stod(t); }
void re(ld& d) { str t; re(t); d = stold(t); }
tcTUU> void re(T& t, U&… u) { re(t); re(u…); }

tcT> void re(complex& c) { T a,b; re(a,b); c = {a,b}; }
tcTU> void re(pair<T,U>& p) { re(p.f,p.s); }
tcT> void re(V& x) { trav(a,x) re(a); }
tcT> void rv(int n, V& x) { x.rsz(n); re(x); }

//OUTPUT
tcT> void pr(V& x) { FOR(i,sz(x)) cout << x[i] << " \n"[i + 1 == sz(x)];}
tcT> void pr(T x) { cout << ts(x); }
tcT> void ps() { cout << ‘\n’; }

void setF(string fileName = “”) {
ios_base::sync_with_stdio(0); cin.tie(0);
if((int)fileName.size()) {
freopen((fileName+".in").c_str(), “r”, stdin);
freopen((fileName+".out").c_str(), “w”, stdout);
}
}

struct DSU {
vector e;
DSU(int N) { e = vector(N, -1); }

int get(int x) { return e[x] < 0 ? x : e[x] = get(e[x]); }

bool same_set(int a, int b) { return get(a) == get(b); }

int size(int x) { return -e[get(x)]; }

bool unite(int x, int y) {  // union by size
	x = get(x), y = get(y);
	if (x == y) return false;
	if (e[x] > e[y]) swap(x, y);
	e[x] += e[y]; e[y] = x;
	return true;
}

};
struct edge{
int a;
int b;
int w;
};

ll bpow(ll x, ll y){
x %= MOD;
ll res = 1LL;
while(y){
if (y & 1LL)
res = x;
res %= MOD;
x = (xx) % MOD;
y >>= 1LL;
}
return res;
}

ll gauss(int n){ return n*(n+1)/2; }

ll fact(int x){if(x) return x * (x - 1); return 1;}
/*
scanf("%lld", &testInteger);
printf("%lld", testInteger);

||f |||l |||o |||p |||p ||||y ||
||||||||||||||||||||
|/|/|/|/|/||/|

**/
vvi A;
vb B;
vi a,b;
int64 ans,c1,c2;

int64 pt(int64 x){
return x * x * 1ll;
}

void dfs1(int i,vi& x){
B[i] = true;
x.pb(i);
trav(z,A[i]) if(!B[z]) dfs1(z,x);
}

void dfs(int i){
B[i] = true;
auto x = lb(all(a),i) - a.begin();
auto y = lb(all(b),i) - b.begin();
auto k = x; if(x) --k;
auto z = y; if(y) --z;

c1 = min({pt(i - a[x]),pt(i - a[k]),c1});
c2 = min({pt(i - b[z]),pt(i - b[y]),c2});

trav(n,A[i]) if(!B[n]) dfs(n);
}

void solve(){
int N,M; cin >> N >> M;
A.clear(); B.clear(); a.clear(); b.clear();
ans = INF;
A.rsz(N); B.rsz(N);

while(M--){
	int x,y; cin >> x >> y;
	--x,--y;
	A[x].pb(y);
	A[y].pb(x);
	} 

	
cout << ans << '\n';
}

main()
{ setIO();
int T = 1; cin >> T;
while(T–) solve();
}

#2