HDU-1827 Summer Holiday

#include <map>
#include <set>
#include <cmath>
#include <ctime>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
#define ll long long
#define file(a) freopen(a".in","r",stdin); freopen(a".out","w",stdout);

inline int gi()
{
    bool b=0; int r=0; char c=getchar();
    while(c<‘0‘ || c>‘9‘) { if(c==‘-‘) b=!b; c=getchar(); }
    while(c>=‘0‘ && c<=‘9‘) { r=r*10+c-‘0‘; c=getchar(); }
    if(b) return -r; return r;
}

const int inf = 1e9+7, N = 1007, M = 2007;
int n,m,num,cnt,Deep,f[N],dfn[N],low[N],bl[N],V[N],C[N],rd[N];
bool b[N];
stack <int> s;
struct data
{
    int fr,nx,to;
}da[M];

inline void add (int fr,int to)
{
    da[++num].fr=fr, da[num].to=to, da[num].nx=f[fr], f[fr]=num;
}

inline void tarjan (int o)
{
    int i,to;
    dfn[o]=low[o]=++Deep;
    s.push(o); b[o]=1;
    for (i=f[o]; i; i=da[i].nx)
        {
            to=da[i].to;
            if (!dfn[to]) tarjan (to), low[o]=min(low[o],low[to]);
            else if (b[to]) low[o]=min(low[o],dfn[to]);
        }
    if (low[o] == dfn[o])
        {
            cnt++;
            do
                {
                    to=s.top(); s.pop(); b[to]=0;
                    bl[to]=cnt; V[cnt]=min(V[cnt],C[to]);
                }
            while(to != o);
        }
}

int main()
{
//    file("HDU-1827");
    int i,x,y;
    while (scanf ("%d%d",&n,&m) != EOF)
        {
            for (i=1; i<=n; i++) C[i]=gi(), V[i]=inf;
            for (i=1; i<=m; i++)
                {
                    x=gi(), y=gi();
                    add (x,y);
                }
            for (i=1; i<=n; i++) if(!dfn[i]) tarjan (i);
            for (i=1; i<=num; i++)
                {
                    x=bl[da[i].fr], y=bl[da[i].to];
                    if (x != y) rd[y]++;
                }
            x=0, y=0;
            for (i=1; i<=cnt; i++) if (!rd[i]) x++, y+=V[i];
            printf ("%d %d\n",x,y);
            for (i=1; i<=n; i++) f[i]=C[i]=V[i]=dfn[i]=low[i]=bl[i]=0;
            for (i=1; i<=cnt; i++) rd[i]=0;
            for (i=1; i<=num; i++) da[i]={ 0,0,0 };
            num=Deep=cnt=0;
        }
    return 0;
}