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using namespace std;
int parent[5000] = { 0 };
int rank[5000] = { 0 };
int person, relative, ask;
void initializeparent()
{
for (int i = 0; i < person; i++)
{
parent[i] = -1;
::rank[i] = 0;
}
}
int find_parent(int x)
{
int x_root = x;
while (parent[x_root] != -1)
{
x_root = parent[x_root];
}
return x_root;
}
int union_(int x, int y)
{
int x_root = find_parent(x);
int y_root = find_parent(y);
if (x_root == y_root)
return 0;
if (::rank[x_root] > ::rank[y_root])
{
parent[y_root] = x_root;//请注意这里一定是这样而不是parent[y] = x;这是血一般的教训啊QAQ
}
else if (::rank[x_root] < ::rank[y_root])
{
parent[x_root] = y_root;
}
else
{
parent[x_root] = y_root;
::rank[y_root]++;
}
return 1;
}
int main()
{
int a, b;
cin >> person >> relative >> ask;
initializeparent();
for (int i = 0; i < relative; i++)
{
cin >> a >> b;
union_(a, b);
}
for (int i = 0; i < ask; i++)
{
cin >> a >> b;
int x_root = find_parent(a);
int y_root = find_parent(b);
if (x_root == y_root)
cout << "Yes" << endl;
else
cout << "No" << endl;
}
return 0;
}
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