Integer Division

If one integer divides another in a subexpression then type of that subexpression is INTEGER. Confusion often arises about integer division; in short, division of two integers produces an integer result by truncation (towards zero).

Consider,

    REAL :: a, b, c, d, e
    a = 1999/1000
    b = -1999/1000
    c = (1999+1)/1000
    d = 1999.0/1000
    e = 1999/1000.0

• a is (about) 1.000. The integer expression 1999/1000 is evaluated and then truncated towards zero to produce an integral value, 1. Its says in the Fortran 90 standard, [1], P84 section 7.2.1.1, ``The result of such an operation [integer division] is the integer closest to the mathematical quotient and between zero and the mathematical quotient inclusively.''
• b is (about) -1.000 for the same reasons as above.
• c is (about) 2.000 because, due to the parentheses 2000/1000 is calculated.
• d and e are (about) 1.999 because both RHS's are evaluated to be real numbers, in 1999.0/1000 and 1999/1000.0 the integers are promoted to real numbers before the division.

Now try this question

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