Example IX

Write an algorithm and flow diagram for adding natural numbers. Natural numbers are positive integers in the set {1, 2, 3, ... infinity}. The set of natural numbers in mathematics is denoted by the capital letter N. The set is often extended by the zero number, in which case it is denoted by N₀. The limit value up to which the computer can be added depends on the capabilities of the processor and the software for programming.

Algorithm:

start
-----------------------------------------------------
X=0
SUM = 0
Input N
X = X + 1
SUM = SUM + X
  If X < N
  Then go back to 'X = X + 1'
Print SUM
-----------------------------------------------------
end

Flowchart:

Program code:

-------------------------------------- 10 CLS 20 CLEAR 30 X = 0: sum = 0 40 INPUT "Input aggregate limit:" N DO X = X + 1 sum = sum + X LOOP WHILE X < N REM Using 'LOOP UNTIL' at first REM complied the condition REM goes out of the loop 50 PRINT "Sum is:" sum 60 END -------------------------------------- 10 CLS 20 CLEAR 30 x = 0: sum = 0 40 INPUT "Input aggregate limit:" N FOR i = 1 TO N STEP 1 x = x + 1 sum = sum + x NEXT i 50 PRINT "Sum is:" sum 60 END --------------------------------------

Example X

Write an algorithm and flowchart that loads N integers. Calculate the sum of all positive and the sum of all negative numbers.

Algorithm:

start
-----------------------------------------------------
Input N
number = 0
positive = 0
negative = 0
Input X
If X > 0
  Then positive = positive + X
  Else negative = negative + x
number = number + 1
If number < N 
  Then go back to 'Input X'
Print positive, negative
-----------------------------------------------------
end

Flowchart:

Program code:

10 CLS 20 CLEAR 30 number = 0 40 positive = 0 50 negative = 0 60 INPUT "Input aggregate limit:" N DO INPUT "Input larger of limit:" X IF X > 0 THEN positive = positive + X ELSE negative = negative + X END IF number = number + 1 LOOP WHILE X < N REM Using 'LOOP UNTIL' at first REM complied the condition REM goes out of the loop 70 PRINT "Sum of positive:" positive 80 PRINT "Sum of negative:" negative 90 END

The listed ten examples were written with the programming tool that has not been 'live' for a long time, but is easy to understand. If by any chance the traffic of these pages increases, this may be a motive to expand these pages with the contents of some other programming tool. The algorithm and flowchart are the same, but the implementation and selection of programming tools depends primarily on the type of device and OS, and there are quite a few newer tools for programming.