Submission #690981

#	Time	Username	Problem	Language	Result	Execution time	Memory
690981		divad	Shell (info1cup18_shell)	C++14	0 / 100	64 ms	31704 KiB

shell

#include <bits/stdc++.h>
#define MOD 1000000007
#define MAX 1000002
using namespace std;
int n,m,p,x,y,d[MAX],dp[MAX],c[MAX],vf[MAX];
vector<int> v[MAX];
vector<int> mrc;

void dfs(int nod){
    vf[nod] = 1;
    for(int vecin: v[nod]){
        if(vf[vecin] == 0){
            d[vecin] = 1+dp[nod];
            dfs(vecin);
        }
    }
}

void dfs_dp(int nod, int src, int dest){
    vf[nod] = 1;
    for(int vecin: v[nod]){
        if(vf[vecin] == 0 && d[vecin] >= d[nod] || (vecin == dest || c[vecin] == 0)){
            dp[vecin] += dp[nod];
            dp[vecin] %= MOD;
            dfs_dp(vecin, src, dest);
        }
    }
}

int nr_drum(int src, int dest){
    memset(dp, 0, sizeof(dp));
    memset(vf, 0, sizeof(vf));
    dp[src] = 1;
    dfs_dp(src, src, dest);
    return dp[dest];
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cin >> n >> m >> p;
    for(int i = 1; i <= p; i++){
        cin >> x;
        mrc.push_back(x);
        c[x] = 1;
    }
    for(int i = 1; i <= m; i++){
        cin >> x >> y;
        v[x].push_back(y);
    }
    d[1] = 1;
    dfs(1);
    for(int i = 1; i < mrc.size(); i++){
        if(d[mrc[i-1]] < d[mrc[i]]){
            cout << "0\n";
            return 0;
        }
    }
    int ans = 0;
    if(mrc[0] != 1){
        ans += nr_drum(1, mrc[0]);
    }else{
    }
    for(int i = 1; i < mrc.size(); i++){
        ans += nr_drum(mrc[i-1], mrc[i]);
        ans %= MOD;
    }
    if(mrc.back() != n){
        ans += nr_drum(mrc.back(), n);
        ans %= MOD;
    }
    cout << ans;
    return 0;
}

Compilation message (stderr)

shell.cpp: In function 'void dfs_dp(int, int, int)':
shell.cpp:22:27: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   22 |         if(vf[vecin] == 0 && d[vecin] >= d[nod] || (vecin == dest || c[vecin] == 0)){
      |            ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
shell.cpp: In function 'int main()':
shell.cpp:54:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |     for(int i = 1; i < mrc.size(); i++){
      |                    ~~^~~~~~~~~~~~
shell.cpp:65:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |     for(int i = 1; i < mrc.size(); i++){
      |                    ~~^~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 45
• Subtask 3: 0 / 20
• Subtask 4: 0 / 25