From 004098143287aa1b18800ca937525af24c31a4cf Mon Sep 17 00:00:00 2001
From: Segcolt <9hmbzr275@mozmail.com>
Date: Tue, 24 Sep 2024 09:41:49 -0300
Subject: [PATCH] First problem uploaded here.

I am stupid, I made a struct that ordenates everything
into a different way, but then I forgot to change the
variables on the dijkstra loop to the correct order and
ended up screwing everything...

At least I'm sure I won't be doing this mistake again in
the future.
---
 .gitignore                           |   2 +
 CSES Problem Set/Flight Discount.cpp | 142 +++++++++++++++++++++++++++
 2 files changed, 144 insertions(+)
 create mode 100644 CSES Problem Set/Flight Discount.cpp

diff --git a/.gitignore b/.gitignore
index e257658..98e855c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -32,3 +32,5 @@
 *.out
 *.app
 
+# Ignore testcases files from competitest
+*.testcases
diff --git a/CSES Problem Set/Flight Discount.cpp b/CSES Problem Set/Flight Discount.cpp
new file mode 100644
index 0000000..95e2edb
--- /dev/null
+++ b/CSES Problem Set/Flight Discount.cpp	
@@ -0,0 +1,142 @@
+/* Problem URL: https://cses.fi/problemset/task/1195 */
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (size_t i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (size_t i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+struct node {
+public:
+    int no;
+    ll cost;
+    int used;
+    
+    node(int no, long long cost, int used) : no(no), cost(cost), used(used) {}
+    
+    auto operator<(node &n) const->bool {
+        return cost < n.cost;
+    }
+    
+    auto operator>(node &n) const->bool {
+        return cost > n.cost;
+    }
+};
+ 
+vvl dist;
+V<V<pair<int, ll>>> graph;
+ 
+long long dijkstra(int n)
+{
+    priority_queue<node, V<node>, greater<>> pq;
+    pq.emplace(0, 0, 0);
+    dist[0][0] = 0;
+    dist[0][1] = 0;
+    
+    while (!pq.empty()) {
+        auto [v, u, b] = pq.top(); pq.pop();
+        
+        if (dist[v][b] < u) {
+            continue;
+        }
+        
+        for (auto [n, c] : graph[v]) {
+            if (u + c < dist[n][b]) {
+                dist[n][b] = u + c;
+                pq.emplace(n, dist[n][b], b);
+            }
+            if (b == 0 && u + (c / 2) < dist[n][1]) {
+                dist[n][1] = u + (c / 2);
+                pq.emplace(n, dist[n][1], 1)    ;
+            }
+        }
+    }
+    
+    return min(dist[n - 1][0], dist[n - 1][1]);
+}
+ 
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+    
+    int n, m;
+    cin >> n >> m;
+    
+    dist.assign(n, vl(2, INT64_MAX));
+    graph.resize(n);
+    
+    while (m--) {
+        long long a, b, c;
+        cin >> a >> b >> c;
+        a--, b--;
+        graph[a].emplace_back(b, c);
+    }
+    
+    cout << dijkstra(n) << '\n';
+ 
+    return 0;
+}