hihocoder 1175 拓扑排序·二

#include <map>
#include <set>
#include <cmath>
#include <queue>
#include <stack>
#include <vector>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <iostream>
#include <algorithm>

using namespace std;
const int maxn = 1e5+10;
const int mod = 142857;

int main(){
int n,m,k,a[maxn],inDeg[maxn],u,v,viru[maxn];
vector<int>vec[maxn];
queue<int>q;
while(~scanf("%d%d%d",&n,&m,&k)){
for(int i = 0;i <= n;i++){
vec[i].clear();
viru[i] = 0;
}
while(!q.empty()) q.pop();
while(k--){
int x;
scanf("%d",&x);
viru[x]++;
}
while(m--){
scanf("%d%d",&u,&v);
inDeg[v]++;
vec[u].push_back(v);
}
for(int i = 1;i <= n;i++){
if(inDeg[i] == 0) q.push(i);
}

while(!q.empty()){
int now = q.front();
q.pop();
for(int i = 0;i < vec[now].size();i++){
if(--inDeg[vec[now][i]] == 0) q.push(vec[now][i]);
viru[vec[now][i]] = (viru[vec[now][i]]+viru[now])%mod;
}
}
int ans = 0;
for(int i = 1;i <= n;i++) ans = (ans+viru[i])%mod;
printf("%d\n",ans);
}
return 0;
}