Writing a Function
As an example, we’ll write a function to determine the factorial of a given number. The factorial of a number n
is the product of the numbers from 1 through n
. The factorial of 5, for example, is 120.
1 * 2 * 3 * 4 * 5 = 120
We might define this function as follows:
// factorial of val is val * (val - 1) * (val - 2) . . . * ((val - (val - 1)) * 1)int fact(int val){ int ret = 1; // local variable to hold the result as we calculate it while (val > 1) ret *= val--; // assign ret * val to ret and decrement val return ret; // return the result}
Our function is named fact
. It takes one int
parameter and returns an int
value. Inside the while
loop, we compute the factorial using the postfix decrement operator ...
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