diff options
-rw-r--r-- | balance_bst.c | 17 | ||||
-rw-r--r-- | balance_bst.py | 0 | ||||
-rw-r--r-- | find_centre_star_graph.c | 34 | ||||
-rw-r--r-- | find_centre_star_graph.py | 27 |
4 files changed, 78 insertions, 0 deletions
diff --git a/balance_bst.c b/balance_bst.c new file mode 100644 index 0000000..e6cdb28 --- /dev/null +++ b/balance_bst.c @@ -0,0 +1,17 @@ +// 1382. Balance a Binary Search Tree +#include "leetcode.h" + +/* + * given the 'root' of a binary search tree, return a balanced binary search + * tree with the same node values. if there is more than one answer, return any + * of them. a binary search tree is balanced if the depth of the two subtrees of + * every node never differs by more than 1. + */ + +struct TreeNode { + int val; + struct TreeNode *left; + struct TreeNode *right; +}; + +struct TreeNode *balanceBST(struct TreeNode *root) {} diff --git a/balance_bst.py b/balance_bst.py new file mode 100644 index 0000000..e69de29 --- /dev/null +++ b/balance_bst.py diff --git a/find_centre_star_graph.c b/find_centre_star_graph.c new file mode 100644 index 0000000..2114d99 --- /dev/null +++ b/find_centre_star_graph.c @@ -0,0 +1,34 @@ +// 1791. Find Center of Star Graph +#include "leetcode.h" + +/* + * there is an undirected star graph consisting of 'n' nodes labeled from 1 to + * 'n'. a star graph is a graph where there is one centre node and exactly 'n - + * 1' edges that connect the centre node with every other node. you are given a + * 2d integer array 'edges' where 'edges[i] = [ui, vi]' indicates that there is + * an edge between the node 'ui' and 'vi'. return the centre of the star graph. + */ + +int findCenter(int **edges, int edgesSize, int *edgesColSize) { + int centre = 0, col = 0, candidate = edges[0][col], n = 0; + for (int i = 0; i < edgesSize; i++) { + for (int j = 0; j < edgesColSize[i]; j++) + if (candidate == edges[i][j]) { + centre = edges[i][j]; + n++; + } + if (i == edgesSize - 1 && n < edgesSize) { + i = 0; + candidate = edges[0][col + 1]; + } + } + return centre; +} + +int main() { + int e1[3][2] = {{1, 2}, {2, 3}, {4, 2}}, + e2[4][2] = {{1, 2}, {5, 1}, {1, 3}, {1, 4}}; + int ecs1 = 3, ecs2 = 4; + printf("%d\n", findCenter((int **)e1, ARRAY_SIZE(e1), &ecs1)); // expect: 2 + printf("%d\n", findCenter((int **)e2, ARRAY_SIZE(e2), &ecs2)); // expect: 1 +} diff --git a/find_centre_star_graph.py b/find_centre_star_graph.py new file mode 100644 index 0000000..8a21109 --- /dev/null +++ b/find_centre_star_graph.py @@ -0,0 +1,27 @@ +# 1791. Find Center of Star Graph + +""" +there is an undirected star graph consisting of 'n' nodes labeled from 1 to +'n'. a star graph is a graph where there is one centre node and exactly 'n - +1' edges that connect the centre node with every other node. you are given a +2d integer array 'edges' where 'edges[i] = [ui, vi]' indicates that there is +an edge between the node 'ui' and 'vi'. return the centre of the star graph. +""" + + +class Solution(object): + def findCenter(self, edges): + """ + :type edges: List[List[int]] + :rtype: int + """ + x, y = edges[0][0], edges[0][1] + if x == edges[1][0] or x == edges[1][1]: + return x + return y + + +if __name__ == "__main__": + obj = Solution() + print(obj.findCenter(edges=[[1, 2], [2, 3], [4, 2]])) + print(obj.findCenter(edges=[[1, 2], [5, 1], [1, 3], [1, 4]])) |