#include <cstdio> #include <algorithm> using namespace std; int N; int origin[500001], target[500001]; int main() { while (scanf("%d",&N)){ if (!N) break; for (int i=0; i<N; i++) scanf("%d %d",&origin[i],&target[i]); if (N % 2) { printf("NO\n"); continue; } sort(origin, origin+N, cmp); sort(target, target+N, cmp); bool yes = 1; for (int i=0; i<N; i++) if (origin[i] != target[i]) yes = 0; printf("%s\n", yes ? "YES" : "NO"); } return 0; }