## Cilk keywords

    cilk_scope {}
    cilk_spawn f();
    cilk_spawn {}
    cilk_sync;
    cilk_for () {}
    int cilk_reducer() x;

## Full example

    #include <cilk/cilk.h>
    #include <vector>

    int fib_cilk_scope(int n) {
    	if (n < 2)
    		return;
    	int x, y;
    	cilk_scope {
    		x = cilk_spawn fib(n-1);
    		y = fib(n-2);
    	}
    	return x + y;

    int fib_cilk_sync(int n) {
    	if (n < 2)
    		return;
    	int x = cilk_spawn fib(n-1);
    	int y = fib(n-2);
    	cilk_sync;
    	return x + y;
    }

    void zero(void *v) {
    	*(int *)v = 0;
    }
    void plus(void *l, void *r) {
    	*(int *)l += *(int *)r;
    }
    int array_sum_cilk_for_reducer(std::vector<int> A) {
    	int cilk_reducer(zero, plus) sum = 0;
    	cilk_for (auto itr = A.cbegin(); itr != A.cend(); ++itr)
    		sum += *itr;
    	return sum;
    }