int maxKilledEnemies(vector<vector<char>>& grid) {
// start coding at 1:32
if (!grid.size() || !grid[0].size()) return 0;
vector<vector<int>> inRow(grid.size(), vector<int>(grid[0].size(), 0));
vector<vector<int>> inCol(grid.size(), vector<int>(grid[0].size(), 0));
for (int i = 0; i < grid.size(); i++) {
unordered_map<int, int> temp;
int wall = -1;
temp[wall] = 0;
for (int j = 0; j < grid[0].size(); j++) {
if (grid[i][j] == 'W') { wall = j; continue; }
if (grid[i][j] == '0') continue;
if (grid[i][j] == 'E') temp[wall]++;
}
for (auto t : temp) {
for (int k = t.first + 1; k < grid[0].size(); k++) inRow[i][k] = t.second;
if (t.first >= 0) inRow[i][t.first] = 0;
}
}
for (int j = 0; j < grid[0].size(); j++) {
unordered_map<int, int> temp;
int wall = -1;
temp[wall] = 0;
for (int i = 0; i < grid.size(); i++) {
if (grid[i][j] == 'W') { wall = i; continue; }
if (grid[i][j] == '0') continue;
if (grid[i][j] == 'E') temp[wall]++;
}
for (auto t : temp) {
for (int k = t.first + 1; k < grid.size(); k++) inCol[k][j] = t.second;
if (t.first >= 0) inCol[t.first][j] = 0;
}
}
int ans = 0;
for (int i = 0; i < grid.size(); i++) for (int j = 0; j < grid[0].size(); j++) {
if (grid[i][j] == 'E') continue;
ans = max(ans, inRow[i][j] + inCol[i][j]);
}
return ans;
}
//check if numberToCheck is valid for the cell
bool Puzzle::isValid(int currentRow, int currentColumn, int numberToCheck)
{
return (!inRow(currentRow, numberToCheck) && !inColumn(currentColumn, numberToCheck) && !inRegion(currentRow, currentColumn, numberToCheck));
}