ywei89

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
class Solution {
public:

ywei89

class Solution {
public:
    int uniquePathsWithObstacles(vector<vector<int> > &obstacleGrid) {
        int numRows = obstacleGrid.size();
        int numCols = obstacleGrid[0].size();
        
        if (numRows == 0 || numCols == 0 ||
            obstacleGrid[numRows - 1][numCols - 1] == 1) { // ignoring this will lead to an erroneous solution
            return 0;
        }

ywei89

class Solution {
public:
    int uniquePaths(int m, int n) {
        int pathCount[m][n];
        memset(pathCount, 0, sizeof(pathCount));
        pathCount[m - 1][n - 1] = 1;
        for (int i = n - 1; i >= 0; i--) { // col
            for (int j = m - 1; j >= 0; j--) { // row
                if (j + 1 < m) { // to the right
                    pathCount[j][i] += pathCount[j + 1][i];

ywei89

/**
 * Definition for binary tree
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
class Solution {

ywei89

class Solution {
public:
    int removeDuplicates(int A[], int n) {
        if (n == 0) return 0; // to prevent the function from outputing 1 for an empty list
        int i = 0;
        int j = 1;
        for (; j < n; j++) {
            if (A[j] != A[i]) A[++i] = A[j];
        }
        return i + 1;