编辑代码

class Main {

    public static int fib(int n){
        int fn = 1;
        int fn_1 = 0;
        for(int i=0; i<n; i++) {
            int t = fn;
            fn = fn + fn_1;
            fn_1 = t;
        }
        return fn;
    }

	public static void main(String[] args) {
		System.out.println(fib(5));
	}
}