1 files changed, 56 insertions, 0 deletions
diff --git a/challenge-192/roger-bell-west/rust/ch-2.rs b/challenge-192/roger-bell-west/rust/ch-2.rs
new file mode 100755
index 0000000000..7517d1f1aa
--- /dev/null
+++ b/challenge-192/roger-bell-west/rust/ch-2.rs
@@ -0,0 +1,56 @@
+#! /bin/sh
+//usr/bin/env rustc --test $0 -o ${0}x && ./${0}x --nocapture; rm -f ${0}x ; exit
+
+use std::cmp::min;
+
+#[test]
+fn test_ex1() {
+    assert_eq!(equaldistribution(vec![1, 0, 5]), 4);
+}
+
+#[test]
+fn test_ex2() {
+    assert_eq!(equaldistribution(vec![0, 2, 0]), -1);
+}
+
+#[test]
+fn test_ex3() {
+    assert_eq!(equaldistribution(vec![0, 3, 0]), 2);
+}
+
+fn equaldistribution(list: Vec<isize>) -> isize {
+    let s = list.iter().sum::<isize>();
+    let l = list.len() as isize;
+    if s % l != 0 {
+        return -1;
+    }
+    let m = s / l;
+    let mut out = 0;
+    let mut w = list.clone();
+    loop {
+        for i in 0..w.len() - 1 {
+            if w[i] > m {
+                let v = w[i] - m;
+                w[i + 1] += v;
+                out += v;
+                w[i] = m;
+            } else if w[i] < m {
+                let v = min(m - w[i], w[i + 1]);
+                w[i + 1] -= v;
+                out += v;
+                w[i] += v;
+            }
+        }
+        let mut done = true;
+        for v in &w {
+            if *v != m {
+                done = false;
+                break;
+            }
+        }
+        if done {
+            break;
+        }
+    }
+    out
+}