唯一程式設計題
給出n個三角形的端點序號，詢問重合三角形的最大集合有多少個三角形？
依次計算兩兩之間的關係，使用並查集獲取連通塊求解
int maxConnectedTrianglesSize(vector<vector<int> >& indexArray, int n) {
vector<int> f(n);
for (int i = 0; i < n; i++) {
f[i] = i;
}
function<int(int)> findx = [&](int y) {
if (f[y] == y) return y;
else return f[y] = findx(f[y]);
};
function<void(int, int)> merge = [&](int a, int b) {
int xa = findx(a), xb = findx(b);
if (xa == xb) return;
f[xa] = xb;
};
function<bool(vector<int>, vector<int>)> check = [&](vector<int> a, vector<int>b) {
unordered_map<int, int> mp;
int tmp = 0;
for (int i:a) {
mp[i] = 1;
}
for (int i:b) {
if (mp.count(i)) tmp++;
}
if (tmp >= 2) return true;
else return false;
};
for (int i = 0; i < n; i++) {
for (int j = i + 1; j < n; j++) {
if (check(indexArray[i],indexArray[j])) merge(i,j);
}
}
unordered_map<int, int> t;
int res = 0;
for (int i = 0; i < n; i++) {
if (t.count(findx(i))) t[findx(i)] += 1;
else t[findx(i)] = 1;
res = max(res, t[findx(i)]);
}
return res;
}