remove aoc solutions

examples/euler/euler_21.zr

@@ -0,0 +1,21 @@
+func divisors_sum[n: i64] : i64
+    k := n
+    sum := 1
+
+    for i in 2..k+1
+        p := 1
+        while k % i == 0
+            p = p * i
+            k = k / i
+        sum = sum * (p * i - 1) / (i - 1)
+    return sum - n
+
+func main[] : i64
+    sum := 0
+
+    for i in 2..10000
+        d := divisors_sum(i)
+        if i < d && i == divisors_sum(d)
+            sum += i + d
+    
+    io.println_i64(sum)