two-sum

Author: u2

Cargo.lock

@@ -0,0 +1,43 @@
+pub fn two_sum(nums: &[usize], target: usize) -> Option<[usize;2]> {
+    let len = nums.len();
+    if len < 2 { return None };
+    let mut i = 0;
+    let mut j = 1;
+    let result: Option<[usize;2]>;
+    loop {
+        if nums[i] + nums[j] == target {
+            result = Some([i, j]);
+            break;
+        }
+        j = j + 1;
+        if j == len {
+            i = i + 1;
+            j = i + 1;
+        }
+        if i == len - 1 {
+            result = None;
+            break;
+        }
+    }
+    return result;
+}
+
+#[cfg(test)]
+mod test {
+    use super::two_sum;
+
+    #[test]
+    fn test_two_sum() {
+        assert_eq!(two_sum(&[2, 7, 11, 15], 18), Some([1,2]));
+
+        assert_eq!(two_sum(&[3,2,4], 6), Some([1,2]));
+
+        assert_eq!(two_sum(&[3,2,4], 7), Some([0,2]));
+
+        assert_eq!(two_sum(&[3,2,4], 8), None);
+
+        assert_eq!(two_sum(&[3,2,11, 3], 5), Some([0,1]));
+
+        assert_eq!(two_sum(&[3], 5), None);
+    }
+}

src/first.rs

@@ -1,6 +1 @@
-#[cfg(test)]
-mod tests {
-    #[test]
-    fn it_works() {
-    }
-}
+pub mod first;