update

src/6/T238883.cpp

@@ -0,0 +1,3 @@
+int main(){
+    
+}

src/6/T434502.cpp

@@ -0,0 +1,94 @@
+#include <iostream>
+#include <vector>
+#include <stack>
+using namespace std;
+
+typedef long long ll;
+const int MAXN = 200010;
+
+int n;
+ll a[MAXN];
+int lc[MAXN], rc[MAXN];
+
+struct State {
+    int u;
+    ll base;
+    int state;
+    ll min_val;
+    ll new_base;
+    ll temp_ans;
+};
+
+int main() {
+    ios::sync_with_stdio(false);
+    cin.tie(0);
+
+    cin >> n;
+    for (int i = 0; i < n; i++) {
+        cin >> a[i];
+    }
+
+    vector<int> stk;
+    int root = -1;
+    for (int i = 0; i < n; i++) {
+        lc[i] = rc[i] = -1;
+    }
+
+    for (int i = 0; i < n; i++) {
+        int last = -1;
+        while (!stk.empty() && a[stk.back()] > a[i]) {
+            last = stk.back();
+            stk.pop_back();
+        }
+        if (stk.empty()) {
+            root = i;
+        } else {
+            rc[stk.back()] = i;
+        }
+        lc[i] = last;
+        stk.push_back(i);
+    }
+
+    stack<State> states;
+    states.push({root, 0, 0, 0, 0, 0});
+    ll ans = 0;
+
+    while (!states.empty()) {
+        State cur = states.top();
+        states.pop();
+
+        if (cur.state == 0) {
+            cur.min_val = a[cur.u] - cur.base;
+            cur.new_base = cur.base;
+            if (cur.min_val > 0) {
+                cur.new_base += cur.min_val;
+            }
+            cur.state = 1;
+            states.push(cur);
+
+            if (lc[cur.u] != -1) {
+                states.push({lc[cur.u], cur.new_base, 0, 0, 0, 0});
+            }
+        } else if (cur.state == 1) {
+            cur.state = 2;
+            states.push(cur);
+
+            if (rc[cur.u] != -1) {
+                states.push({rc[cur.u], cur.new_base, 0, 0, 0, 0});
+            }
+        } else {
+            ll add = (cur.min_val > 0) ? 1 : 0;
+            ll total_ans = add + cur.temp_ans;
+
+            if (states.empty()) {
+                ans = total_ans;
+            } else {
+                State& parent = states.top();
+                parent.temp_ans += total_ans;
+            }
+        }
+    }
+
+    cout << ans << endl;
+    return 0;
+}