Added Network Delay Time Structure

Author: ryanoneill

src/network_delay_time.rs

@@ -0,0 +1,54 @@
+/// You are given a network of `n` nodes, labeled from `1` to `n`. You are also
+/// given `times`, a list of travel times as directed edges
+/// `times[i] = (ui, vi, wi)`, where `ui` is the source node, `vi` is the
+/// target node, and `wi` is the time it takes for a signal to travel from
+/// source to target.
+///
+/// We will send a signal from a given node `k`. Return the minimum time it
+/// takes for all the `n` nodes to receive the signal. If it is impossible for
+/// all the `n` nodes to receive the signal, return `-1`.
+struct Solution;
+
+impl Solution {
+
+    // TODO: Implement
+    pub fn network_delay_time(times: Vec<Vec<i32>>, n: i32, k: i32) -> i32 {
+        0
+    }
+
+}
+
+#[cfg(test)]
+mod tests {
+    use super::Solution;
+
+    #[ignore]
+    #[test]
+    fn example_1() {
+        let times = vec![vec![2,1,1], vec![2,3,1], vec![3,4,1]];
+        let n = 4;
+        let k = 2;
+        let result = Solution::network_delay_time(times, n, k);
+        assert_eq!(result, 2);
+    }
+
+    #[ignore]
+    #[test]
+    fn example_2() {
+        let times = vec![vec![1,2,1]];
+        let n = 2;
+        let k = 1;
+        let result = Solution::network_delay_time(times, n, k);
+        assert_eq!(result, 1);
+    }
+
+    #[test]
+    fn example_3() {
+        let times = vec![vec![1,2,1]];
+        let n = 2;
+        let k = 2;
+        let result = Solution::network_delay_time(times, n, k);
+        assert_eq!(result, -1);
+    }
+
+}