#include #include using namespace std; int main(){ int n, v; cin >> n; vector t(n + 1); atcoder::dsu uf(n); for(int i = 0; i < n; i++){ cin >> v; uf.merge(--v, i); } auto G = uf.groups(); for(auto c:G) t[c.size()]++; for(int i = 2; i <= n; i+=2){ if(t[i] & 1){ cout << "No" << endl; return 0; } } cout << "Yes" << endl; }