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authorJack Sangdahl <[email protected]>2025-03-10 00:36:13 -0600
committerJack Sangdahl <[email protected]>2025-03-10 00:36:13 -0600
commit7c60dee83b436e8e8a667bf9f191beced8de4fc3 (patch)
treeeb7a24ee2067f92245c57bb118e85a1baf15df50 /other/snakes_ladders.cpp
parent5d7cdc215e4ba1ec4cbb24c084cccb5e5e641468 (diff)
downloadleetcode-7c60dee83b436e8e8a667bf9f191beced8de4fc3.tar.gz
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chore: move cpp and rust code to directory
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+// 909. Snakes and Ladders
+#include "leetcode.h"
+
+typedef pair<int, int> pii;
+class Solution {
+public:
+ int snakesAndLadders(vvd & board) {
+ int rows = board.size(), cols = board[0].size();
+ int target = rows * cols, r, c, p;
+ vector<int> visited(rows * cols + 1); // cells on board starting from 1
+ priority_queue<pii, vector<pii>, greater<pii>> pq;
+ pq.push(make_pair(0, 1));
+ visited[1] = true;
+ while (pq.size()) {
+ auto stepPos = pq.top();
+ pq.pop();
+ int s = stepPos.first / 1000 + 1;
+ for (int i = 1; i <= 6; i++) {
+ auto p = stepPos.second + i;
+ if (visited[p])
+ continue;
+ visited[p] = true;
+ r = rows - (p - 1) / cols - 1;
+ c = (p - 1) % cols;
+ if ((rows - r - 1) % 2)
+ c = cols - c - 1;
+ int ladder = board[r][c];
+ if (ladder > 0 && ladder <= target)
+ p = ladder;
+ if (p == target)
+ return s;
+ pq.push(make_pair(s * 1000 + 500 - p, p));
+ }
+ }
+ return -1;
+ }
+};
+
+int main() {
+ Solution obj;
+ vvd board1 = {{-1, -1, -1, -1, -1, -1}, {-1, -1, -1, -1, -1, -1},
+ {-1, -1, -1, -1, -1, -1}, {-1, 35, -1, -1, 13, -1},
+ {-1, -1, -1, -1, -1, -1}, {-1, 15, -1, -1, -1, -1}};
+ vvd board2 = {{-1, -1}, {-1, 3}};
+ cout << obj.snakesAndLadders(board1) << endl; // expect: 4
+ cout << obj.snakesAndLadders(board2) << endl; // expect: 1
+}