LEADZ — Number of leading zero bits of an integer

Description

LEADZ returns the number of leading zero bits of an integer.

Syntax

RESULT = LEADZ(I)

Arguments

I Shall be of type INTEGER.

Return value

The type of the return value is the default INTEGER. If all the bits of I are zero, the result value is BIT_SIZE(I).

Example


PROGRAM test_leadz
  WRITE (*,*) BIT_SIZE(1) ! prints 32
  WRITE (*,*) LEADZ(1) ! prints 31
END PROGRAM

Standard

Fortran 2008 and later

Class

Elemental function

See also

BIT_SIZE, TRAILZ, POPCNT, POPPAR