Submission #1750018

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Source Code Expand

#include<bits/stdc++.h>
using namespace std;

int N,X;
int F[100010] = {0};
int ans = 0;
vector<int> G[100010];

int DFS(int v,int p)
{
    int res = 0;
    for(int i = 0; i < G[v].size(); i++)if(G[v][i] != p)if(DFS(G[v][i],v)){ans += 2;res = 1;}
    if(F[v])res++;
    return res;
}

int main()
{
    scanf("%d%d",&N,&X);
    for(int i = 1; i <= N; i++)scanf("%d",F + i);
    for(int i = 0; i < N - 1; i++)
    {
        int a,b;
        scanf("%d%d",&a,&b);
        G[a].push_back(b);
        G[b].push_back(a);
    }

    DFS(X,-1);
    printf("%d\n",ans);
    return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:19:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d",&N,&X);
                        ^
./Main.cpp:20:49: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     for(int i = 1; i <= N; i++)scanf("%d",F + i);
                                                 ^
./Main.cpp:24:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d",&a,&b);
                            ^

Judge Result