UCF Local Programming Contest 2014

E

判断是否有死循环

#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <set>
#include <queue>
#include <map>
#include <sstream>
#include <cstdio>
#include <cstring>
#include <numeric>
#include <cmath>
#include <iomanip>
#include <deque>
#include <bitset>
#define ll              long long
#define PII             pair<int, int>
#define rep(i,a,b)      for(int  i=a;i<=b;i++)
#define dec(i,a,b)      for(int  i=a;i>=b;i--)
#define pb              push_back
#define mk              make_pair
using namespace std;
int dir[4][2] = { { 0,1 } ,{ 0,-1 },{ 1,0 },{ -1,0 } };
const long long INF = 0x7f7f7f7f7f7f7f7f;
const int inf = 0x3f3f3f3f;
const double pi = 3.14159265358979323846;
const int mod = 998244353;
const int N = 50 + 5;
//if(x<0 || x>=r || y<0 || y>=c)

inline ll read()
{
    ll x = 0; bool f = true; char c = getchar();
    while (c < '0' || c > '9') { if (c == '-') f = false; c = getchar(); }
    while (c >= '0' && c <= '9') x = (x << 1) + (x << 3) + (c ^ 48), c = getchar();
    return f ? x : -x;
}

ll gcd(ll m, ll n)
{
    return n == 0 ? m : gcd(n, m % n);
}
ll lcm(ll m, ll n)
{
    return m * n / gcd(m, n);
}

int main()
{
    int t;
    cin >> t;
    rep(q, 1, t)
    {
        int p, s;
        cin >> p >> s;
        vector<string> name(p + 1);
        vector<vector<int>> g(p + 1,vector<int>(p+1,0));
        rep(i, 1, p)
        {
            cin >> name[i];
        }
        rep(i, 1, p)
        {
            int n;
            cin >> n;
            rep(j, 1, n)
            {
                int t;
                cin >> t;
                g[i][t] = 1;
            }
        }
        rep(i, 1, p)
        {
            rep(j, 1, p)
            {
                rep(k, 1, p)
                {
                    g[j][k] |= g[j][i] & g[i][k];
                }
            }
        }
        vector<bool> cycle(p + 1,0);
        rep(i, 1, p)
        {
            if (g[i][i])
                cycle[i] = 1;
        }
        vector<bool> infi(p + 1,0);
        rep(i, 1, p)
        {
            if (g[s][i] && cycle[i])
                infi[i] = 1;
        }
        bool change = 1;
        while (change)
        {
            change = 0;
            rep(i, 1, p)
            {
                if (infi[i])
                {
                    rep(j, 1, p)
                    {
                        if (g[i][j] && !infi[j])
                        {
                            infi[j] = 1;
                            change = 1;
                        }
                    }
                }
            }
        }
        int cnt = 0;
        rep(i, 1, p)
        {
            if (infi[i])
                cnt++;
        }
        if (cnt == 0)
            cout << "Chain Email #" << q << ":
" << "Safe chain email!" << endl;
        else
        {
            cout << "Chain Email #" << q << ":" << endl;
            rep(i, 1, p)
            {
                if (infi[i])
                    cout << name[i] << " ";
            }
            cout << endl;
        }
        cout << endl;
    }
    return 0;
}

J

对阶乘计算

#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <set>
#include <queue>
#include <map>
#include <sstream>
#include <cstdio>
#include <cstring>
#include <numeric>
#include <cmath>
#include <iomanip>
#include <deque>
#include <bitset>
#define ll              long long
#define PII             pair<int, int>
#define rep(i,a,b)      for(int  i=a;i<=b;i++)
#define dec(i,a,b)      for(int  i=a;i>=b;i--)
#define pb              push_back
#define mk              make_pair
using namespace std;
int dir[4][2] = { { 0,1 } ,{ 0,-1 },{ 1,0 },{ -1,0 } };
const long long INF = 0x7f7f7f7f7f7f7f7f;
const int inf = 0x3f3f3f3f;
const double pi = 3.14159265358979323846;
const int mod = 998244353;
const int N = 50 + 5;
//if(x<0 || x>=r || y<0 || y>=c)

inline ll read()
{
    ll x = 0; bool f = true; char c = getchar();
    while (c < '0' || c > '9') { if (c == '-') f = false; c = getchar(); }
    while (c >= '0' && c <= '9') x = (x << 1) + (x << 3) + (c ^ 48), c = getchar();
    return f ? x : -x;
}

ll gcd(ll m, ll n)
{
    return n == 0 ? m : gcd(n, m % n);
}
ll lcm(ll m, ll n)
{
    return m * n / gcd(m, n);
}

int main()
{
    int t;
    cin >> t;
    rep(q, 1, t)
    {
        int p, s;
        cin >> p >> s;
        vector<string> name(p + 1);
        vector<vector<int>> g(p + 1,vector<int>(p+1,0));
        rep(i, 1, p)
        {
            cin >> name[i];
        }
        rep(i, 1, p)
        {
            int n;
            cin >> n;
            rep(j, 1, n)
            {
                int t;
                cin >> t;
                g[i][t] = 1;
            }
        }
        rep(i, 1, p)
        {
            rep(j, 1, p)
            {
                rep(k, 1, p)
                {
                    g[j][k] |= g[j][i] & g[i][k];
                }
            }
        }
        vector<bool> cycle(p + 1,0);
        rep(i, 1, p)
        {
            if (g[i][i])
                cycle[i] = 1;
        }
        vector<bool> infi(p + 1,0);
        rep(i, 1, p)
        {
            if (g[s][i] && cycle[i])
                infi[i] = 1;
        }
        bool change = 1;
        while (change)
        {
            change = 0;
            rep(i, 1, p)
            {
                if (infi[i])
                {
                    rep(j, 1, p)
                    {
                        if (g[i][j] && !infi[j])
                        {
                            infi[j] = 1;
                            change = 1;
                        }
                    }
                }
            }
        }
        int cnt = 0;
        rep(i, 1, p)
        {
            if (infi[i])
                cnt++;
        }
        if (cnt == 0)
            cout << "Chain Email #" << q << ":
" << "Safe chain email!" << endl;
        else
        {
            cout << "Chain Email #" << q << ":" << endl;
            rep(i, 1, p)
            {
                if (infi[i])
                    cout << name[i] << " ";
            }
            cout << endl;
        }
        cout << endl;
    }
    return 0;
}