def sod(divisor, limit):
last = (limit - (limit - 1) % divisor) // divisor
return last * (last + 1) // 2 * divisor
print(sod(3, 1000) + sod(5, 1000) - sod(15, 1000))
ZGVmIHNvZChkaXZpc29yLCBsaW1pdCk6CglsYXN0ID0gKGxpbWl0IC0gKGxpbWl0IC0gMSkgJSBkaXZpc29yKSAvLyBkaXZpc29yCglyZXR1cm4gbGFzdCAqIChsYXN0ICsgMSkgLy8gMiAqIGRpdmlzb3IKCnByaW50KHNvZCgzLCAxMDAwKSArIHNvZCg1LCAxMDAwKSAtIHNvZCgxNSwgMTAwMCkp