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use pathfinding::undirected::prim::prim;
#[test]
// Simple example taken from the test used in kruskal implementation
fn base_test() {
let edges = vec![
('a', 'b', 3),
('a', 'e', 1),
('b', 'c', 5),
('b', 'e', 4),
('c', 'd', 2),
('c', 'e', 6),
('d', 'e', 7),
];
assert_eq!(
prim(&edges),
vec![
(&'a', &'e', 1),
(&'a', &'b', 3),
(&'b', &'c', 5),
(&'c', &'d', 2),
]
);
}
#[test]
// Taken from https://www.geeksforgeeks.org/prims-minimum-spanning-tree-mst-greedy-algo-5/
fn geeksforgeeks() {
let edges = vec![
(0, 1, 4),
(0, 7, 8),
(1, 2, 8),
(1, 7, 11),
(2, 3, 7),
(2, 5, 4),
(2, 8, 2),
(3, 4, 9),
(3, 5, 14),
(4, 5, 10),
(5, 6, 2),
(6, 7, 1),
(6, 8, 6),
(7, 8, 7),
];
assert_eq!(
prim(&edges),
vec![
(&0, &1, 4),
(&0, &7, 8),
(&7, &6, 1),
(&6, &5, 2),
(&5, &2, 4),
(&2, &8, 2),
(&2, &3, 7),
(&3, &4, 9),
]
);
}
// Order of edges is not important in the result, except for starting edge, because always
// starting vertex of the first edge will be selected as the start in algorithm
#[test]
fn another_test() {
let edges = vec![
('B', 'C', 10),
('B', 'D', 4),
('C', 'D', 2),
('A', 'C', 3),
('C', 'D', 2),
('D', 'E', 1),
('C', 'E', 6),
('D', 'E', 1),
];
assert_eq!(
prim(&edges),
vec![
(&'B', &'D', 4),
(&'D', &'E', 1),
(&'D', &'C', 2),
(&'C', &'A', 3),
]
);
}