八皇后变题hash

lc336

lc1001

hash计灯在行列、正负对角线的覆盖次数，查询时判断目标格是否被照亮，随后关闭查询格周围3×3区域的灯并更新统计

class Solution {
public:
unordered_map<int, int> ver, hor;
unordered_map<int, int> d1, d2;
set<pair<int,int>> st;

void add(pair<int,int> pr) {
if(st.count(pr))return;
ver[pr.first]++;
hor[pr.second]++;
d1[pr.first+pr.second]++;
d2[pr.first-pr.second]++;
st.insert(pr);
}

void close(pair<int,int> pr) {
ver[pr.first]--;
hor[pr.second]--;
d1[pr.first+pr.second]--;
d2[pr.first-pr.second]--;
st.erase(pr);
}

int query(pair<int,int> pr) {
return ver[pr.first] > 0 || hor[pr.second] > 0 || d1[pr.first+pr.second] > 0 || d2[pr.first-pr.second] > 0;
}

vector<int> gridIllumination(int N, vector<vector<int>>& lamps, vector<vector<int>>& queries) {
for(auto e: lamps)
add(make_pair(e[0], e[1]));

vector<int> ans;
for(auto e: queries)

{
int x = e[0], y = e[1];
ans.push_back(query(make_pair(x,y)));
for(int i = -1 ; i <= 1 ; i++) {
for(int j = -1 ; j <= 1 ; j++) {
if(st.count(make_pair(x+i, y+j)))
close(make_pair(x+i,y+j));
}
}
}
return ans;
}
};