Leetcode 62: Unique Paths - recursive O(n!)

leetcode_62a.cpp

#include <iostream>

using namespace std;

void walk(int x, int y, int sizex, int sizey, int& count) {
    //end condition is x,y are bottom right, so count++ and return
    if (x == sizex-1 && y == sizey-1) {
        count++;
        return;
    }

    //attempt to go down if room
    if (y < sizey-1)
        walk(x, y+1, sizex, sizey, count);

    //attempt to walk right if room
    if (x < sizex-1)
        walk(x+1, y, sizex, sizey, count);
}

int uniquePaths(int m, int n) {
    int count = 0;
    walk(0, 0, m, n, count);
    return count;
}

int main() {
    cout << uniquePaths(23, 12) << "\n";

    return 0;
}