Submission #1081380

#	Time	Username	Problem	Language	Result	Execution time	Memory
1081380		cpptowin	Paths (BOI18_paths)	C++17	100 / 100	326 ms	119124 KiB

paths

#include <bits/stdc++.h>
#define fo(i, d, c) for (int i = d; i <= c; i++)
#define fod(i, c, d) for (int i = c; i >= d; i--)
#define maxn 1000010
#define N 1010
#define fi first
#define se second
#define pb emplace_back
#define en cout << "\n";
#define int long long
#define inf (int)1e18
#define bitcount(x) __builtin_popcountll(x)
#define pii pair<int, int>
#define vii vector<pii>
#define lb(x) x & -x
#define bit(i, j) ((i >> j) & 1)
#define offbit(i, j) (i ^ (1LL << j))
#define onbit(i, j) (i | (1LL << j))
#define vi vector<int>
#define all(x) x.begin(), x.end()
#define ss(x) (int)x.size()
template <typename T1, typename T2>
bool minimize(T1 &a, T2 b)
{
    if (a > b)
    {
        a = b;
        return true;
    }
    return false;
}
template <typename T1, typename T2>
bool maximize(T1 &a, T2 b)
{
    if (a < b)
    {
        a = b;
        return true;
    }
    return false;
}
using namespace std;
const int nsqrt = 450;
const int mod = 1e9 + 7;
void add(int &x, int k)
{
    x += k;
    x %= mod;
    if (x < 0)
        x += mod;
}
void del(int &x, int k)
{
    x -= k;
    x %= mod;
    if (x < 0)
        x += mod;
}
int n, m, k, a[maxn];
vi ke[maxn];
bool vis[maxn];
int f[maxn][33];
int par[maxn];
// void dfs(int u)
// {
//     f[u][1 << a[u]] = 1;
//     vis[u] = 1;
//     for (int v : ke[u])
//     {
//         if (!vis[v])
//         {
//             par[v] = u;
//             dfs(v);
//             fo(mask, 0, 31) if (!bit(mask, a[u]))
//             {
//                 f[u][onbit(mask, a[u])] += f[v][mask];
//             }
//         }
//     }
// }
main()
{
#define name "TASK"
    if (fopen(name ".inp", "r"))
    {
        freopen(name ".inp", "r", stdin);
        freopen(name ".out", "w", stdout);
    }
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> n >> m >> k;
    fo(i, 1, n) cin >> a[i], a[i]--,f[i][1 << a[i]] = 1;
    fo(i, 1, m)
    {
        int u, v;
        cin >> u >> v;
        ke[u].pb(v);
        ke[v].pb(u);
    }
    // dfs(1);
    // fo(u, 1, n)
    // {
    //     for (int v : ke[u])
    //         if (par[v] != u)
    //         {
    //             fo(mask, 0, 31) if (!bit(mask, a[u]))
    //             {
    //                 f[u][onbit(mask, a[u])] += f[v][mask];
    //             }
    //         }
    // }
    fo(mask,1,(1 << k) - 1) 
    {
        fo(u,1,n) 
        {
            for(int v : ke[u]) 
            {
                f[u][mask] += f[v][offbit(mask,a[u])];
            }
        }
    }
    // cout << f[2][6];
    // en;
    int res = 0;
    fo(i, 1, n) fo(mask, 0, 31) if (bitcount(mask) > 1) if (f[i][mask])
    {
        // cout << i << ' ' << mask << ' ' << f[i][mask] << "\n";
        res += f[i][mask];
    }
    cout << res;
}

Compilation message (stderr)

paths.cpp:81:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   81 | main()
      | ^~~~
paths.cpp: In function 'int main()':
paths.cpp:86:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   86 |         freopen(name ".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
paths.cpp:87:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   87 |         freopen(name ".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 23 / 23
• Subtask 2: 20 / 20
• Subtask 3: 27 / 27
• Subtask 4: 30 / 30