✅

P7912 100pts 队列 (used to be using vector, TLE)

bears-fruit-basket/data.in

@@ -0,0 +1,2 @@
+12
+1 1 0 0 1 1 1 0 1 1 0 0

bears-fruit-basket/main.cc

@@ -0,0 +1,68 @@
+#include <iostream>
+#include <vector>
+#include <queue>
+
+using namespace std;
+
+struct fruit {
+    int type;
+    int start;
+    int end;
+
+    fruit(int t, int start, int end) {
+        this->type = t;
+        this->start = start;
+        this->end = end;
+    }
+};
+
+bool took[200000 + 5], fruits[200000 + 5];
+
+int main() {
+    int n;
+    queue<fruit> blocks, pending_blocks;
+    cin >> n;
+    for (int i = 1; i <= n; i++) {
+        cin >> fruits[i];
+    }
+    fruits[n + 1] = !fruits[n]; // Make the last block can be handled
+    for (int ptr = 2, lead = 1; ptr <= n + 1; ptr++) {
+        if (fruits[ptr] != fruits[ptr - 1]) {
+            blocks.emplace(fruits[ptr - 1], lead, ptr - 1);
+            lead = ptr;
+        }
+    }
+    // 1st -> 1 1 0 0 1 1 1 0 1 1 0 0
+    //        x   x   x   x x   x
+    // 2nd ->   1   0   1     1   0 0
+    int remain = n;
+    while (remain) {
+        while (!blocks.empty()) {
+            auto front = blocks.front();
+            blocks.pop();
+            while (took[front.start] && front.start <= front.end) front.start++;
+            if (front.start > front.end) continue;
+            printf("%d ", front.start);
+            remain--;
+            took[front.start] = true;
+            if (front.end == front.start) continue;
+            front.start++;
+            pending_blocks.push(front);
+        }
+        printf("\n");
+        while (!pending_blocks.empty()) {
+            auto front = pending_blocks.front();
+            pending_blocks.pop();
+            while (!pending_blocks.empty()) {
+                auto back = pending_blocks.front();
+                if (front.type == back.type) {
+                    front.end = back.end;
+                    pending_blocks.pop();
+                } else {
+                    break;
+                }
+            }
+            blocks.push(front);
+        }
+    }
+}