diff --git a/031/main.rs b/031/main.rs
new file mode 100644
index 0000000..b80b577
--- /dev/null
+++ b/031/main.rs
@@ -0,0 +1,22 @@
+fn cs(n: u32, cl: usize) -> u32 {
+    let coins = [1, 2, 5, 10, 20, 50, 100, 200];
+    if n == 0 { return 1; }
+    if cl == 0 { return 1; }
+    let mut res = cs(n, cl - 1);
+    //println!("init {}/{}/{}", n, cl, res);
+    let mc = coins[cl];
+    let mut m = n;
+    //println!("m vs mc: {}/{}", m, mc);
+    while m >= mc {
+        res += cs(m - mc, cl - 1);
+        //println!("res({}, {})+= {}", m-mc, cl-1, res);
+        m -= mc;
+    }
+    res
+}
+
+fn main() {
+    let res = cs(200, 7);
+    println!("{}", res);
+}
+