MLE and WA

2023204/main.cpp

@@ -1,57 +1,126 @@
 #include <stdio.h>
-#include <vector>
 #define DEAD false
 #define ALIVE true
 // 'Natural count' is the name of the node when all the nodes in the tree is
 // alive. xxx_num denotes the count as the question described.
 
+// SEE ALSO BRANCH 04_02 WITH A CORRECT IMPLEMENTATION 
+
 int ans[200] = {0};
 long long dead_nodes_num[105] = {0};
 int total_dead_nodes = 0;
 long long target_nodes_num[105] = {0};
 int total_target_nodes = 0;
-long long max_spawned_num = 0;
 
-struct Layer {
+struct SeveralContinuedDeadNode {
-    long long start_num;
+    bool status;
-    long long end_num;
+    long long length; // Caution that when status == dead and length == 1, the node itself is alive.
-    std::vector<long long> dead_nodes;
 };
 
-Layer tree[150] = {0};
+struct SearchResult {
+    int next_ans_pos;               // pos in the ans[] array.
+    long long count_in_father_line; // natural count.
+};
 
-void create_tree(long long start_num, long long prev_alive, int layer, int next_dead_node_ptr) {
+SearchResult find_node(long long target, long long start_num, int next_dead_node_num_ptr,
-    tree[layer].start_num = start_num;
+                       SeveralContinuedDeadNode *upper_line, long long upper_line_segment_count,
-    prev_alive *= 2;
+                       int layer) {
-    tree[layer].end_num = start_num + prev_alive - 1;
+    long long spawned_node_max_num = start_num - 1;
-    while (next_dead_node_ptr < total_dead_nodes &&
+    long long segment_count = upper_line_segment_count;
-           dead_nodes_num[next_dead_node_ptr] <= tree[layer].end_num) {
+    SeveralContinuedDeadNode current_line_node[200] = {0};
-        tree[layer].dead_nodes.push_back(dead_nodes_num[next_dead_node_ptr++]);
+    long long current_line_len = 0;
-        prev_alive--;
+    bool all_dead = true;
-    }
-    if (prev_alive == 0 || tree[layer].end_num >= target_nodes_num[total_target_nodes - 1]) {
-        max_spawned_num = tree[layer].end_num;
-        return;
-    }
 
-    create_tree(tree[layer].end_num + 1, prev_alive, layer + 1, next_dead_node_ptr);
+    // Spawing all the nodes in current line
-}
+    for (int upper_line_iter = 0; upper_line_iter < upper_line_segment_count; upper_line_iter++) {
+        if (upper_line[upper_line_iter].status == DEAD) {
+            current_line_node[current_line_len] = upper_line[upper_line_iter];
+            current_line_node[current_line_len].length *= 2;
+            current_line_len++;
+        }
+        else {
+            all_dead = false;
+            long long total_spawned_after =
+                spawned_node_max_num + upper_line[upper_line_iter].length * 2;
+            while (dead_nodes_num[next_dead_node_num_ptr] <= total_spawned_after &&
+                   next_dead_node_num_ptr < total_dead_nodes) {
+                if (dead_nodes_num[next_dead_node_num_ptr] - spawned_node_max_num > 1) {
+                    current_line_node[current_line_len] = SeveralContinuedDeadNode{
+                        ALIVE, dead_nodes_num[next_dead_node_num_ptr] - spawned_node_max_num - 1};
+                    current_line_len++; // things before this new dead node
+                }
+                current_line_node[current_line_len] =
+                    SeveralContinuedDeadNode{DEAD, 1}; // this new dead node
+                current_line_len++;
 
-void find_ans(long long target, int layer) {
+                spawned_node_max_num = dead_nodes_num[next_dead_node_num_ptr]; // we now spawned to
-    ans[layer] = target;
+                                                                               // this dead node.
-    if (layer == 1) {
+                next_dead_node_num_ptr++;
-        return;
+            }
-    }
+            if (spawned_node_max_num < total_spawned_after) {
-    long long count_in_layer = (target - tree[layer].start_num) / 2;
+                current_line_node[current_line_len] =
-    for (int i = 0; i < tree[layer - 1].dead_nodes.size(); i++) {
+                    SeveralContinuedDeadNode{ALIVE, total_spawned_after - spawned_node_max_num};
-        if (count_in_layer < tree[layer - 1].dead_nodes[i] - tree[layer - 1].start_num - i) {
+                current_line_len++;
-            find_ans(tree[layer - 1].start_num + i + count_in_layer, layer - 1);
+            }
-            return;
+
+            spawned_node_max_num = total_spawned_after;
         }
     }
-    // til the end_num
+
-    find_ans(tree[layer - 1].start_num + tree[layer - 1].dead_nodes.size() + count_in_layer,
+    if (all_dead) {
-             layer - 1);
+        return SearchResult{1, -1};
+    }
+
+    if (target <= spawned_node_max_num) {
+        ans[0] = target;
+        long long natural_pos = -1, num = start_num - 1;
+        for (int i = 0; i < current_line_len; i++) {
+            if (current_line_node[i].status == DEAD) {
+                natural_pos += current_line_node[i].length;
+                num += (current_line_node[i].length == 1);
+                if (num == target) {
+                    return SearchResult{1, natural_pos / 2};
+                }
+                continue;
+            }
+
+            // Now deal with alive nodes
+            if (num + current_line_node[i].length < target) {
+                natural_pos += current_line_node[i].length;
+                num += current_line_node[i].length;
+            }
+            else {
+                // if we made it here, then the target > num + current_line_node[i].length
+                return SearchResult{1, (natural_pos + target - num) / 2};
+            }
+        }
+        return SearchResult{1, -1};
+    }
+    else {
+        SearchResult current_line_pos =
+            find_node(target, spawned_node_max_num + 1, next_dead_node_num_ptr, current_line_node,
+                      current_line_len, layer + 1);
+        if (current_line_pos.count_in_father_line < 0) {
+            // The path does not exist.
+            return SearchResult{1, -1};
+        }
+
+        long long natural_count = -1, num = start_num - 1;
+        for (int i = 0; i < current_line_len; i++) {
+            natural_count += current_line_node[i].length;
+            if (current_line_node[i].status == ALIVE || current_line_node[i].length == 1) {
+                num += current_line_node[i].length;
+            }
+
+            if (natural_count >= current_line_pos.count_in_father_line) {
+                num -= natural_count - current_line_pos.count_in_father_line;
+                ans[current_line_pos.next_ans_pos++] = num;
+                break;
+            }
+        }
+        return SearchResult{current_line_pos.next_ans_pos,
+                            current_line_pos.count_in_father_line / 2};
+    }
 }
 
 int main() {
@@ -62,13 +131,11 @@ int main() {
     for (int i = 0; i < total_target_nodes; i++) {
         scanf("%lld", &target_nodes_num[i]);
     }
-
-    tree[1].start_num = 1;
-    tree[1].end_num = 1;
     if (dead_nodes_num[0] == 1) {
         for (int i = 0; i < total_target_nodes; i++) {
             if (target_nodes_num[i] == 1) {
-                printf("1\n"); //
+                printf("1\n");
+                continue;
             }
             else {
                 printf("0\n");
@@ -76,25 +143,21 @@ int main() {
         }
         return 0;
     }
-
+    else {
-    create_tree(2, 1, 2, 0);
+        SeveralContinuedDeadNode firstline = SeveralContinuedDeadNode{ALIVE, 1};
-
+        for (int i = 0; i < total_target_nodes; i++) {
-    // printf("Max spawn: %lld\n", max_spawned_num);
+            SearchResult result = find_node(target_nodes_num[i], 2, 0, &firstline, 1, 2);
-
+            if (result.count_in_father_line == -1) {
-    for (int i = 0; i < total_target_nodes; i++) {
+                printf("0\n");
-        if (target_nodes_num[i] > max_spawned_num) {
+            }
-            printf("0\n");
+            else {
-            continue;
+                printf("1 ");
+                for (int j = result.next_ans_pos - 1; j >= 0; j--) {
+                    printf("%lld ", ans[j]);
+                }
+                printf("\n");
+            }
         }
-        int layer_pos = 1;
-        while (tree[layer_pos].end_num < target_nodes_num[i]) {
-            layer_pos++;
-        }
-        find_ans(target_nodes_num[i], layer_pos);
-        for (int j = 1; j <= layer_pos; j++) {
-            printf("%lld ", ans[j]);
-        }
-        printf("\n");
     }
 
     return 0;

2023205/main.cpp

@@ -0,0 +1,71 @@
+#include <stdio.h>
+// 并查集。并查集只关注双向连通性。
+
+struct Edge {
+    unsigned short end;
+    int next;
+};
+
+Edge edges[1050000];
+char nodes_visited[65540];
+int head[65540], len;
+
+int add_edge(int start, int terminal) {
+    edges[++len].end = terminal;
+    edges[len].next = head[start];
+    head[start] = len;
+    return 0;
+}
+
+int dfs(int start) {
+    if (nodes_visited[start] >= 1) {
+        nodes_visited[start] = 2;
+        return 0;
+    }
+    nodes_visited[start] = 1;
+    for (int j = head[start]; j != 0; j = edges[j].next) {
+        dfs(edges[j].end);
+    }
+    return 0;
+}
+
+int main() {
+    int N, M;
+    scanf("%d %d", &N, &M);
+    for (int start = 0; start < N; start++) {
+        int edge_count;
+        scanf("%d", &edge_count);
+        for (int j = 0; j < edge_count; j++) {
+            int terminal;
+            scanf("%d", &terminal);
+            add_edge(start, terminal);
+        }
+    }
+    
+    dfs(0);
+
+    for (int i  = 0; i < N; i++) {
+        if (nodes_visited[i] < 1) {
+            // Not connected!
+            for (int j = 0; j <= M; j++) {
+                printf("0\n");
+            }
+            return 0;
+        }
+    }
+
+    printf("1\n");
+
+    for (int i = 0; i < M; i++) {
+        int start, end;
+        scanf("%d %d", &start, &end);
+        if (nodes_visited[end] == 2) {
+            printf("1\n");
+        }
+        else {
+            printf("0\n");
+        }
+    }
+
+    return 0;
+}