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| + | ====== JUI - 5. cviceni ====== | ||
| + | ===== POle ===== | ||
| + | |||
| + | * klasicky - vytvoreni - ''make-array'', | ||
| + | |||
| + | <code lisp> | ||
| + | ;;3-rozmerne pole s dim = 2x4x6 | ||
| + | (setf pole (make-array '(2 4 6) :initial-element nil )) | ||
| + | |||
| + | ;;pristup k prvku | ||
| + | (aref pole 0 2 5) ;vypise nil - nic jsme tam nezaradili | ||
| + | |||
| + | ;;prirazeni | ||
| + | (setf (aref pole 0 2 5) '(1 3) ) | ||
| + | |||
| + | </code> | ||
| + | ===== struktury ===== | ||
| + | <code lisp> | ||
| + | (defstruct Zaznam | ||
| + | (hodnota (progn (princ "Zadej cislo "))) | ||
| + | (levy nil) | ||
| + | pravy | ||
| + | ) | ||
| + | |||
| + | ;;vytvoreni instance | ||
| + | (setf z (make-zaznam)) ; otaze se na jmeno | ||
| + | |||
| + | ;;prirazeni hodnoty | ||
| + | (setf (zaznam-levy z)) | ||
| + | </code> | ||
| + | |||
| + | ===== hashovaci tabulka ===== | ||
| + | * dvojice <klic, hodnota> | ||
| + | * vyhoda: rychle hledani v tabulce) | ||
| + | |||
| + | <code lisp> | ||
| + | ;;vytvoreni; make-hash-table | ||
| + | (setf ht (make-hash-table)) | ||
| + | |||
| + | ;;pristup k prvkum: gethash | ||
| + | |||
| + | (gethash klic ht) - hashuje podle cehokoliv | ||
| + | ;;neexistuje - vraci nil | ||
| + | |||
| + | (setf (gethash 'klic ht) 10) | ||
| + | |||
| + | ;;odstraneni | ||
| + | (remhash 'klic ht) | ||
| + | |||
| + | |||
| + | ;;prochazeni hash tabulkou | ||
| + | maphash funke tabulka - ma 2 parametry: klic, hodnota | ||
| + | |||
| + | ;;pr. vypsani prvku tabulky | ||
| + | (maphash #'(lambda (k h) | ||
| + | (format t "Klic: ~A hodnota: ~A ~%" k h) | ||
| + | ) | ||
| + | ht | ||
| + | ) | ||
| + | </code> | ||
| + | |||
| + | <code lisp> | ||
| + | ;; pomoci hashovaci tabulky spocete cetnost prvku v seznamu | ||
| + | (defun spocti-cetnosti (seznam) | ||
| + | (let (ht) | ||
| + | (setf ht (make-hash-table)) | ||
| + | (mapcar #'(lambda (a) | ||
| + | (setf (gethash a ht) (if (gethash a ht) (+ 1 (gethash a ht)) 1)) | ||
| + | ) | ||
| + | seznam | ||
| + | ) | ||
| + | (maphash #'(lambda (k h) | ||
| + | (format t "Prvek ~A ma cetnost ~A ~%" k h) | ||
| + | ) | ||
| + | ht | ||
| + | ) | ||
| + | ) | ||
| + | ) | ||
| + | |||
| + | |||
| + | ;;mame orientovany acyklicky graf reprezentovany seznamem | ||
| + | ( (a b c) (b c d) (c d) (d)) | ||
| + | ;;zjistit, do jakych uzlu vede cesta | ||
| + | |||
| + | |||
| + | </code> | ||
