// fib_bench.cvm — 递归 fibonacci 性能测试
func fib(n) {
    if (n < 2) return n;
    return fib(n - 1) + fib(n - 2);
}
let t0 = clock_ms();
let r = fib(35);
let t1 = clock_ms();
println("cvm fib(35)=" + str(r) + " time=" + str(t1 - t0) + "ms");