- What is Armstrong number?
- The number which is formed by the sum of cubes of its own digits is Armstrong number.
- Example: 153, 370, 371, 407, etc.
- 153 = 1
^{3}+ 5^{3}+ 3^{3}

= 1 + 125 + 27

= 153

**Qbasic Code**

**Using DO WHILE ..... LOOP**

CLS

INPUT "Enter a number"; n

b = n

DO WHILE n <> 0

r = n MOD 10

a = a + r ^ 3

n = n \ 10

LOOP

IF a = b THEN

PRINT "It is armstrong number";

ELSE

PRINT "It is not armstrong number";

END IF

END

**Using WHILE ... WEND**

CLS

INPUT "ENTER ANY NUMBER"; N

A = N

S = 0

WHILE N <> 0

R = N MOD 10

S = S + R ^ 3

N = N \ 10

WEND

IF A = S THEN

PRINT A; "IS ARMSTRONG"

ELSE

PRINT A; "IS NOT ARMSTRONG"

END IF

END

**Using SUB Procedure**

DECLARE SUB ARM (N)

CLS

INPUT "ENTER ANY NUMBER"; N

CALL ARM(N)

END

SUB ARM (N)

A = N

S = 0

WHILE N <> 0

R = N MOD 10

S = S + R ^ 3

N = N \ 10

WEND

IF A = S THEN

PRINT A; "IS ARMSTRONG NUMBER"

ELSE

PRINT A; "IS NOT ARMSTRONG NUMBER"

END IF

END SUB

**Using Function Procedure**

DECLARE FUNCTION ARM (N)

CLS

INPUT "ENTER ANY NUMBER"; N

A = N

AR = ARM(N)

IF A = AR THEN

PRINT A; "IS ARMSTRONG NUMBER"

ELSE

PRINT A; "IS NOT ARMSTRONG NUMBER"

END IF

END

FUNCTION ARM (N)

S = 0

WHILE N <> 0

R = N MOD 10

S = S + R ^ 3

N = N \ 10

WEND

ARM = S

END FUNCTION