public static void main(String[] args) { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); int[] a = new int[n]; int[] b = new int[n]; for(int i = 0; i < n; i++){ a[i]=sc.nextInt(); } for(int i = 0; i < n; i++){ b[i]=sc.nextInt(); } System.out.println(minMatch(a,b)); } private static int minMatch(int[] a, int[] b) { Arrays.sort(a); Arrays.sort(b); int i=a.length-1; int j=b.length-1; int res = 1; while(i>=0){ if(a[i]>b[j]) return res; else{ i-=2; j--; res+=2; } } return -1; } 我这么写的，ac了