errors

$ cargo build
   Compiling max_flow v0.1.0 (file:///Users/pedro/Documents/Code/max_flow)
src/lib.rs:128:56: 128:65 error: no method named `collect` found for type `BfsIterator<'_, V, i64, fn(_, i64, _) {flow_predicate}>` in the current scope
src/lib.rs:128         BfsIterator::new(self, source, flow_predicate).collect()
                                                                      ^~~~~~~~~
src/lib.rs:128:56: 128:65 note: the method `collect` exists but the following trait bounds were not satisfied: `BfsIterator<'_, V, i64, fn(_, i64, _) {flow_predicate}> : core::iter::Iterator`
src/lib.rs:128:56: 128:65 help: items from traits can only be used if the trait is implemented and in scope; the following trait defines an item `collect`, perhaps you need to implement it:
src/lib.rs:128:56: 128:65 help: candidate #1: `core::iter::Iterator`
error: aborting due to previous error
Could not compile `max_flow`.

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