Submission #467869

#	Time	Username	Problem	Language	Result	Execution time	Memory
467869		stefantaga	Power Plant (JOI20_power)	C++14	0 / 100	3 ms	5068 KiB

power

#include <bits/stdc++.h>

using namespace std;
vector <int> v[200005];
int din[200005][2],val[200005];
void dfs(int x,int tata)
{
    int ok=0,i;
    for (i=0;i<v[x].size();i++)
    {
        if (v[x][i]!=tata)
        {
            ok=1;
            dfs(v[x][i],x);
        }
    }
    if (ok==0)
    {
        if (val[x]==1)
        {
            din[x][1]=1;
            din[x][0]=1;
        }
    }
    else
    {
        if (x==1&&v[x].size()==1)
        {
            din[x][1]=max(din[v[x][0]][0]+1,din[v[x][0]][1]+1);
            din[x][0]=1;
        }
        else
        {
            if (val[x]==0)
        {
            for (i=0;i<v[x].size();i++)
            {
                din[x][0]=din[x][0]+max(din[v[x][i]][0],din[v[x][i]][1]);
            }
        }
        else
        {
            int sum1=0,sum0=0;
            for (i=0;i<v[x].size();i++)
            {
                int nod=v[x][i];
                sum1=sum1+max(din[nod][1],din[nod][0]);
            }
            din[x][1]=sum1-1;
            din[x][0]=1;
        }
        }
    }
}
int n,i,x,y;
char ch;
int main()
{
    ios_base :: sync_with_stdio(false);
    cin.tie(0);
    #ifdef HOME
    ifstream cin("date.in");
    ofstream cout("date.out");
    #endif // HOME
    cin>>n;
    for (i=1;i<=n-1;i++)
    {
        cin>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for (i=1;i<=n;i++)
    {
        cin>>ch;
        val[i]=ch-'0';
    }
    dfs(1,0);
    /*for (i=1;i<=n;i++)
    {
        cout<<i<<" "<<din[i][0]<<" "<<din[i][1]<<'\n';
    }*/
    cout<<max(din[1][0],din[1][1]);
    return 0;
}

Compilation message (stderr)

power.cpp: In function 'void dfs(int, int)':
power.cpp:9:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    9 |     for (i=0;i<v[x].size();i++)
      |              ~^~~~~~~~~~~~
power.cpp:36:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |             for (i=0;i<v[x].size();i++)
      |                      ~^~~~~~~~~~~~
power.cpp:44:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   44 |             for (i=0;i<v[x].size();i++)
      |                      ~^~~~~~~~~~~~
power.cpp:43:24: warning: unused variable 'sum0' [-Wunused-variable]
   43 |             int sum1=0,sum0=0;
      |                        ^~~~

• Subtask 1: 0 / 6
• Subtask 2: 0 / 41
• Subtask 3: 0 / 53