3. Describe what this simple C99 program does and under what circumstances it will return true or false. Explain why it may sometimes be false.

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[])
{
	float f[argc - 1];
	for (int i = 1; i < argc; i++)
		f[i - 1] = atof(argv[i]);  // string to float

	float r1 = 0;
	for (int i = 0; i < argc - 1; i++)
		r1 += f[i];

	float r2 = 0;
	for (int i = argc - 2; i >= 0; i--)
		r2 += f[i];

	return r1 != r2;
}