gistfile1.clj

(def sales-data [
 {:person_id 1
  :deal_id 2
  :date "2013-01-04"}
 {:person_id 1
  :deal_id 3
  :date "2013-01-05"}
 {:person_id 1
  :deal_id 4
  :date "2013-01-05"}
 {:person_id 2
  :deal_id 2
  :date "2013-01-04"}
 {:person_id 2
  :deal_id 3
  :date "2013-01-04"}
 {:person_id 2
  :deal_id 4
  :date "2013-01-05"}
 {:person_id 3
  :deal_id 1
  :date "2013-01-06"}
 {:person_id 4
  :deal_id 2
  :date "2013-01-06"}
 {:person_id 5
  :deal_id 2
  :date "2013-01-05"}
 {:person_id 5
  :deal_id 3
  :date "2013-01-04"}
 {:person_id 6
  :deal_id 4
  :date "2013-01-05"}
])

(defn sales-per-person [data])  ;; {1 3, 2 3, 3 1, 4 1, 5 2, 6 1}
(defn sales-per-deal [data])    ;; {2 4, 3 3, 4 3, 1 1}
(defn sales-per-day [data])     ;; {"2013-01-04" 4, "2013-01-05" 5, "2013-01-06" 2}

(def intervals1 [[1.3 4.5] [2.1 7.8] [0.8 2.3]]) ;; [2.1 2.3]
(def intervals2 [[1.3 3.4] [2.0 4.9] [0.8 1.9]]) ;; []

(defn interval-intersection [intervals]
"Takes a list of ordered pairs [double, double] representing intervals and returns
either the intersection of all the intervals or the empty list."
)

(permute "fred") ;; ("fred" "frde" "ferd" "fedr" "fdre" ...)
(defn permute [string]
"Takes a string and returns all distinct permutations of it."
)