QBASIC Program to get the factorial of a supplied number

DECLARE FUNCTION fact (n)
CLS
INPUT "Supply a number"; n

PRINT "Factorial value of"; n; "is"; fact(n)
END


FUNCTION fact (n)
f = 1
c = 1
WHILE c <= n
f = f * c
c = c + 1
WEND
fact = f
END FUNCTION

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