4. (20 Points) Provide best-case and worst-case running time and space complexity analysis in Big-Oh notation forthe following pow 2 method. Foreach case, provide an example input pair and brief explanation Big-0 Notation Example InputExplanation Best-Case Running Time Worst-Case Running Time Best-Case Space Complexi Worst-Case Space Complexi public static long pow_2(long x, int n) { if (n 0) if (n1) if (n % 2- 0) { return 1 return x; return pow2( x, n/ 2 ) * pow 2( x, n / 2); return pow 2(x * x, n /2) * x; else {