Problem p00120 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <algorithm>
#include <bitset>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <vector>

using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> i_i;

#define PI 3.141592653589793238462643383279
#define mod 1000000007LL
#define rep(i, n) for (i = 0; i < n; ++i)
#define rep1(i, n) for (i = 1; i < n; ++i)
#define per(i, n) for (i = n - 1; i > -1; --i)
#define int(x)                                                                 \\
  int x;                                                                       \\
  scanf("%d", &x)
#define int2(x, y)                                                             \\
  int x, y;                                                                    \\
  scanf("%d%d", &x, &y)
#define int3(x, y, z)                                                          \\
  int x, y, z;                                                                 \\
  scanf("%d%d%d", &x, &y, &z)
#define int4(v, x, y, z)                                                       \\
  int v, x, y, z;                                                              \\
  scanf("%d%d%d%d", &v, &x, &y, &z)
#define int5(v, w, x, y, z)                                                    \\
  int v, w, x, y, z;                                                           \\
  scanf("%d%d%d%d%d", &v, &w, &x, &y, &z)
#define ll2(x, y)                                                              \\
  ll x, y;                                                                     \\
  cin >> x >> y;
#define scn(n, a) rep(i, n) cin >> a[i]
#define sc2n(n, a, b) rep(i, n) cin >> a[i] >> b[i]
#define pri(x) cout << (x) << "\\n"
#define pri2(x, y) cout << (x) << " " << (y) << "\\n"
#define pri3(x, y, z) cout << (x) << " " << (y) << " " << (z) << "\\n"
#define pb push_back
#define mp make_pair
#define all(a) (a).begin(), (a).end()
#define endl "\\n"
#define kabe puts("---------------------------")
#define kara puts("")
#define debug(x) cout << " --- " << (x) << "\\n"
#define debug2(x, y) cout << " --- " << (x) << " " << (y) << "\\n"
#define debug3(x, y, z)                                                        \\
  cout << " --- " << (x) << " " << (y) << " " << (z) << "\\n"
#define X first
#define Y second
#define eps 0.00000001
#define prid(x) printf("%.15lf\\n", x)

double w, r[12];
int hd, dt[12];
double dp[4100][12];

bool solve(void) {
  int i, j, k;
  rep(i, 1 << hd) rep(j, hd) dp[i][j] = 2016.0;
  rep(j, hd) dp[1 << j][j] = r[j];
  rep1(i, 1 << hd) rep(j, hd) if (dp[i][j] != 2016.0)
      rep(k, hd) if ((i & (1 << k)) == 0) dp[i | (1 << k)][k] =
          min(dp[i | (1 << k)][k], dp[i][j] + 2.0 * sqrt(r[j] * r[k]));
  rep(j, hd) if (dp[(1 << hd) - 1][j] + r[j] <= w + eps) return true;
  return false;
}

int pt;
string s;

double nxt(void) {
  int res = 0;
  for (;;) {
    if (s[pt] == ' ')
      break;
    res = (res * 10) + (s[pt++] - '0');
  }
  return (double)res;
}

signed main(void) {
  int i, j;
  for (int testcase = 0; testcase >= 0; testcase++) {
    getline(cin, s);
    if (s.size() == 0)
      break;
    s += " ";
    hd = 0;
    pt = 0;
    w = nxt();
    ++pt;
    for (; pt < s.size();) {
      r[hd++] = nxt();
      ++pt;
    }

    puts(solve() ? "OK" : "NA");

    //*/

    //*/ break;
  }
  return 0;
}

Error: TLE

Fixed submission:

#include <algorithm>
#include <bitset>
#include <climits>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <vector>

using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> i_i;

#define PI 3.141592653589793238462643383279
#define mod 1000000007LL
#define rep(i, n) for (i = 0; i < n; ++i)
#define rep1(i, n) for (i = 1; i < n; ++i)
#define per(i, n) for (i = n - 1; i > -1; --i)
#define int(x)                                                                 \\
  int x;                                                                       \\
  scanf("%d", &x)
#define int2(x, y)                                                             \\
  int x, y;                                                                    \\
  scanf("%d%d", &x, &y)
#define int3(x, y, z)                                                          \\
  int x, y, z;                                                                 \\
  scanf("%d%d%d", &x, &y, &z)
#define int4(v, x, y, z)                                                       \\
  int v, x, y, z;                                                              \\
  scanf("%d%d%d%d", &v, &x, &y, &z)
#define int5(v, w, x, y, z)                                                    \\
  int v, w, x, y, z;                                                           \\
  scanf("%d%d%d%d%d", &v, &w, &x, &y, &z)
#define ll2(x, y)                                                              \\
  ll x, y;                                                                     \\
  cin >> x >> y;
#define scn(n, a) rep(i, n) cin >> a[i]
#define sc2n(n, a, b) rep(i, n) cin >> a[i] >> b[i]
#define pri(x) cout << (x) << "\\n"
#define pri2(x, y) cout << (x) << " " << (y) << "\\n"
#define pri3(x, y, z) cout << (x) << " " << (y) << " " << (z) << "\\n"
#define pb push_back
#define mp make_pair
#define all(a) (a).begin(), (a).end()
#define endl "\\n"
#define kabe puts("---------------------------")
#define kara puts("")
#define debug(x) cout << " --- " << (x) << "\\n"
#define debug2(x, y) cout << " --- " << (x) << " " << (y) << "\\n"
#define debug3(x, y, z)                                                        \\
  cout << " --- " << (x) << " " << (y) << " " << (z) << "\\n"
#define X first
#define Y second
#define eps 0.0001
#define prid(x) printf("%.15lf\\n", x)

double w, r[12];
int hd, dt[12];
bool used[12];
double o[12];

bool dfs(int cnt) {
  int i, j;
  if (cnt == hd) {
    rep(i, hd) {
      o[i] = r[dt[i]];
      rep(j, i) o[i] = max(o[i], o[j] + 2.0 * sqrt(r[dt[i]] * r[dt[j]]));
      if (o[i] + r[dt[i]] > w)
        return false;
    }
    // rep(i, hd)pri2(i, dt[i]);
    return true;
  }
  rep(i, hd) if (!used[i]) {
    dt[cnt] = i;
    used[i] = true;
    if (dfs(cnt + 1))
      return true;
    used[i] = false;
  }
  return false;
}

int pt;
string s;

double nxt(void) {
  int res = 0;
  for (;;) {
    if (s[pt] == ' ')
      break;
    res = (res * 10) + (s[pt++] - '0');
  }
  return (double)res;
}

signed main(void) {
  int i, j;
  for (int testcase = 0; testcase >= 0; testcase++) {
    getline(cin, s);
    if (s.size() == 0)
      break;
    s += " ";
    hd = 0;
    pt = 0;
    w = nxt();
    ++pt;
    for (; pt < s.size();) {
      r[hd++] = nxt();
      ++pt;
    }
    rep(i, hd) used[i] = false;

    // pri(w);rep(i, hd)pri2(i, r[i]);

    // printf("== testcase %d ==\\n", testcase);
    puts(dfs(0) ? "OK" : "NA");

    //*/

    //*/ break;
  }
  return 0;
}