// Method 1
                let mut batch_lower_bound = 0usize;
                while batch_lower_bound + batch_size < examples.len() {
                    batches[i] = &examples[batch_lower_bound..batch_lower_bound + batch_size];
                    batch_lower_bound += batch_size;
                }
                batches[batches.len() - 1] = &examples[batch_lower_bound..examples.len()];

                // Method 2
                let mut batch_lower_bound = 0usize;
                let mut batch_upper_bound = batch_lower_bound + batch_size;
                while batch_upper_bound < examples.len() {
                    batches[i] = &examples[batch_lower_bound..batch_upper_bound];
                    batch_lower_bound = batch_upper_bound;
                    batch_upper_bound += batch_size;
                }
                batches[batches.len() - 1] = &examples[batch_lower_bound..examples.len()];

                // Method 3
                let mut batch_lower_bound = 0usize;
                let batch_upper_bound = || -> usize {batch_lower_bound + batch_size};
                while batch_upper_bound() < examples.len() {
                    batches[i] = &examples[batch_lower_bound..batch_upper_bound()];
                    batch_lower_bound = batch_upper_bound();
                }
                batches[batches.len() - 1] = &examples[batch_lower_bound..examples.len()];