[UVa] 11280 - Flying to Fredericton

Author            : Dipu Kumar Mohanto 
                    CSE, Batch - 6
                    BRUR.
Problem Statement : 11280 - Flying to Fredericton
Source            : UVa Online Judge
Category          : Graph Theory
Algorithm         : Karp's minimum mean weight cycle algorithm
Verdict           : Accepted

#include "bits/stdc++.h"
 
using namespace std;
 
#define FI              freopen("in.txt", "r", stdin)
#define FO              freopen("out.txt", "w", stdout)
#define FAST            ios_base::sync_with_stdio(false), cin.tie(NULL), cout.tie(NULL)
 
#define FOR(i, n)       for (int i = 1; i <= n; i++)
#define For(i, n)       for (int i = 0; i < n; i++)
#define ROF(i, n)       for (int i = n; i >= 1; i--)
#define Rof(i, n)       for (int i = n-1; i >= 0; i--)
#define FORI(i, n)      for (auto i : n)
 
#define ll              long long
#define ull             unsigned long long
#define vi              vector <int>
#define vl              vector <ll>
#define pii             pair <int, int>
#define pll             pair <ll, ll>
#define mk              make_pair
#define ff              first
#define ss              second
#define eb              emplace_back
#define em              emplace
#define pb              push_back
#define ppb             pop_back
#define All(a)          a.begin(), a.end()
#define memo(a, b)      memset(a, b, sizeof a)
#define Sort(a)         sort(All(a))
#define ED(a)           Sort(a), a.erase(unique(All(a)), a.end())
#define rev(a)          reverse(All(a))
#define sz(a)           (int)a.size()
#define max3(a, b, c)   max(a, max(b, c))
#define min3(a, b, c)   min(a, min(b, c))
#define maxAll(a)       *max_element(All(a))
#define minAll(a)       *min_element(All(a))
#define allUpper(a)     transform(All(a), a.begin(), :: toupper)
#define allLower(a)     transform(All(a), a.begin(), :: tolower)
#define endl            '\n'
#define nl              puts("")
#define ub              upper_bound
#define lb              lower_bound
#define Exp             exp(1.0)
#define PIE             2*acos(0.0)
#define Sin(a)          sin(((a)*PIE)/180.0)
#define EPS             1e-9
 
#include "ext/pb_ds/assoc_container.hpp"
#include "ext/pb_ds/tree_policy.hpp"
using namespace __gnu_pbds;
 
template <typename T> using orderset = tree <T, null_type, less <T>, rb_tree_tag, tree_order_statistics_node_update>;
 
#include "ext/rope"
using namespace __gnu_cxx;
 
// rope <int> Rope;
 
// int dr[] = {1, -1, 0, 0}; // 4 Direction
// int dc[] = {0, 0, 1, -1};
// int dr[] = {0, 0, 1, -1, 1, 1, -1, -1}; // 8 Direction
// int dc[] = {1, -1, 0, 0, 1, -1, 1, -1};
// int dr[] = {-1, 1, -2, -2, -1, 1, 2, 2}; // knight Moves
// int dc[] = {-2, -2, -1, 1, 2, 2, 1, -1};
 
#define trace1(x)                           cerr << #x << ": " << x << endl;
#define trace2(x, y)                        cerr << #x << ": " << x << " | " << #y << ": " << y << endl;
#define trace3(x, y, z)                     cerr << #x << ": " << x << " | " << #y << ": " << y << " | " << #z << ": " << z << endl;
#define trace4(a, b, c, d)                  cerr << #a << ": " << a << " | " << #b << ": " << b << " | " << #c << ": " << c << " | " << #d << ": " << d << endl;
#define trace5(a, b, c, d, e)               cerr << #a << ": " << a << " | " << #b << ": " << b << " | " << #c << ": " << c << " | " << #d << ": " << d << " | " << #e << ": " << e << endl;
#define trace6(a, b, c, d, e, f)            cerr << #a << ": " << a << " | " << #b << ": " << b << " | " << #c << ": " << c << " | " << #d << ": " << d << " | " << #e << ": " << e << " | " << #f << ": " << f << endl;
 
inline int setbit(int mask, int pos)        { return mask |= (1 << pos); }
inline int resetbit(int mask, int pos)      { return mask &= ~(1 << pos); }
inline int togglebit(int mask, int pos)     { return mask ^= (1 << pos); }
inline bool checkbit(int mask, int pos)     { return (bool)(mask & (1 << pos)); }
 
#define popcount(mask)                       __builtin_popcount(mask) // count set bit
#define popcountLL(mask)                     __builtin_popcountll(mask) // for long long
 
inline int read()                           { int a; scanf("%d", &a); return a; }
inline ll readLL()                          { ll a; scanf("%lld", &a); return a; }
inline double readDD()                      { double a; scanf("%lf", &a); return a; }
 
template <typename T> string toString(T num) { stringstream ss; ss << num; return ss.str(); }
int toInt(string s)                          { int num; istringstream iss(s); iss >> num; return num;  }
ll toLLong(string s)                         { ll num; istringstream iss(s); iss >> num; return num; }
 
#define inf             123456789
#define mod             1000000007
 
static const int maxn = 1e3 + 5;
static const int logn = 18;
 
struct node
{
    int v, w;
    node(int v = 0, int w = 0) : v(v), w(w) {}
};
 
vector <node> graph[maxn];
int dp[maxn][maxn];
 
inline void karps(int src, int tNode)
{
    memset(dp, inf, sizeof dp);
    dp[0][src] = 0;
    for (int k = 1; k <= tNode; k++)   // how many edges to cross
    {
        for (int u = 1; u <= tNode; u++)   // total node
        {
            for (node e : graph[u])
            {
                int v = e.v;
                int w = e.w;
                if (dp[k - 1][u] != inf)
                {
                    int wt = dp[k - 1][u] + w;
                    dp[k][v] = min(dp[k][v], wt);
                }
            }
        }
    }
}
 
 
inline int getAns(int v, int max_edge)
{
    int ans = inf;
    for (int e = 1; e <= max_edge; e++) ans = min(ans, dp[e][v]);
    return ans;
}
 
map <string, int> Map;
 
int main()
{
//    FI;
    FAST;
    int tc;
    cin >> tc;
    for (int tcase = 1; tcase <= tc; tcase++)
    {
        int tNode;
        cin >> tNode;
        string city;
        int id = 0;
        for (int i = 0; i < tNode; i++)
        {
            cin >> city;
            Map.insert(mk(city, ++id));
        }
        int u = Map["Calgary"];
        int v = Map["Fredericton"];
        int tEdge;
        cin >> tEdge;
        string city1, city2;
        int z;
        for (int e = 0; e < tEdge; e++)
        {
            cin >> city1 >> city2 >> z;
            int x = Map[city1];
            int y = Map[city2];
            graph[x].push_back(node(y, z));
        }
        karps(u, tNode);
        cout << "Scenario #" << tcase << endl;
        int tQuery;
        cin >> tQuery;
        while (tQuery--)
        {
            int stopovers;
            cin >> stopovers;
            int ans = getAns(v, min(stopovers + 1, tNode));
            if (ans == inf) cout << "No satisfactory flights" << endl;
            else cout << "Total cost of flight(s) is $" << ans << endl;
        }
        if (tcase < tc) cout << endl;
        Map.clear();
        for (int i = 0; i < maxn; i++) graph[i].clear();
    }
}