Problem p03004 (C++)

Buggy submission (status: Time Limit Exceeded):
#include <algorithm>
#include <bitset>
#include <cfloat>
#include <deque>
#include <fstream>
#include <functional>
#include <iomanip>
#include <iostream>
#include <limits.h>
#include <list>
#include <map>
#include <math.h>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string.h>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#define rep(i, n) for (int i = 0; i < n; i++)
#define REP(i, n) for (int i = 1; i <= n; i++)
#define int long long
#define ll long long
#define eps DBL_EPSILON
#define mod (ll)998244353
#define INF LLONG_MAX / 10
#define P pair<int, int>
#define prique priority_queue
using namespace std;
int n, x[100010], y[100010];
char d[100010];
long double func(long double time) {
  long double mi = 200000000, ma = -200000000;
  rep(i, n) {
    if (d[i] == 'R') {
      mi = min(mi, x[i] + time);
      ma = max(ma, x[i] + time);
    } else if (d[i] == 'L') {
      mi = min(mi, x[i] - time);
      ma = max(ma, x[i] - time);
    } else {
      mi = min(mi, (long double)x[i]);
      ma = max(ma, (long double)x[i]);
    }
  }
  long double memo = ma - mi;
  mi = 200000000;
  ma = -200000000;
  rep(i, n) {
    if (d[i] == 'U') {
      mi = min(mi, y[i] + time);
      ma = max(ma, y[i] + time);
    } else if (d[i] == 'D') {
      mi = min(mi, y[i] - time);
      ma = max(ma, y[i] - time);
    } else {
      mi = min(mi, (long double)y[i]);
      ma = max(ma, (long double)y[i]);
    }
  }
  return memo * (ma - mi);
}
signed main() {
  cin >> n;
  rep(i, n) cin >> x[i] >> y[i] >> d[i];
  long double ok = 0, ng = 300000000;
  rep(i, 10000) {
    long double md1 = ok + (ng - ok) / 3, md2 = ok + (ng - ok) * 2 / 3;
    if (func(md1) <= func(md2))
      ng = md2;
    else
      ok = md1;
  }
  printf("%.12Lf\n", func(ng));
  return 0;
}

Fixed submission:
#include <algorithm>
#include <bitset>
#include <cfloat>
#include <deque>
#include <fstream>
#include <functional>
#include <iomanip>
#include <iostream>
#include <limits.h>
#include <list>
#include <map>
#include <math.h>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string.h>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#define rep(i, n) for (int i = 0; i < n; i++)
#define REP(i, n) for (int i = 1; i <= n; i++)
#define int long long
#define ll long long
#define eps DBL_EPSILON
#define mod (ll)998244353
#define INF LLONG_MAX / 10
#define P pair<int, int>
#define prique priority_queue
using namespace std;
int n, x[100010], y[100010];
char d[100010];
long double func(long double time) {
  long double mi = 200000000, ma = -200000000;
  rep(i, n) {
    if (d[i] == 'R') {
      mi = min(mi, x[i] + time);
      ma = max(ma, x[i] + time);
    } else if (d[i] == 'L') {
      mi = min(mi, x[i] - time);
      ma = max(ma, x[i] - time);
    } else {
      mi = min(mi, (long double)x[i]);
      ma = max(ma, (long double)x[i]);
    }
  }
  long double memo = ma - mi;
  mi = 200000000;
  ma = -200000000;
  rep(i, n) {
    if (d[i] == 'U') {
      mi = min(mi, y[i] + time);
      ma = max(ma, y[i] + time);
    } else if (d[i] == 'D') {
      mi = min(mi, y[i] - time);
      ma = max(ma, y[i] - time);
    } else {
      mi = min(mi, (long double)y[i]);
      ma = max(ma, (long double)y[i]);
    }
  }
  return memo * (ma - mi);
}
signed main() {
  cin >> n;
  rep(i, n) cin >> x[i] >> y[i] >> d[i];
  long double ok = 0, ng = 300000000;
  rep(i, 500) {
    long double md1 = ok + (ng - ok) / 3, md2 = ok + (ng - ok) * 2 / 3;
    if (func(md1) <= func(md2))
      ng = md2;
    else
      ok = md1;
  }
  printf("%.12Lf\n", func(ng));
  return 0;
}