【題目敘述】https://leetcode.com/problems/kth-smallest-instructions/
class Solution {
public:
string kthSmallestPath(vector<int>& d, int k) {
int n = d[0]+1, m = d[1]+1;
int dp[20][20] = {};
for (int i = 0; i < m; i++){
dp[n-1][i] = 1;
}
for (int i = n-2; i >= 0; i--){
for (int j = m-1; j >= 0; j--){
dp[i][j] = dp[i+1][j]+dp[i][j+1];
}
}
int x = 0, y = 0;
string ans;
for (int i = 0; i < n+m-2; i++){
if (x == n-1){
y++;
ans += 'H';
}
else if (y == m-1){
x++;
ans += 'V';
}
else{
if (k > dp[x][y+1]){
k -= dp[x][y+1];
x++;
ans += 'V';
}
else{
y++;
ans += 'H';
}
}
}
return ans;
}
};