x = int(input()) val = ((1 + 8 * x) ** 0.5 - 1) / 2 line = int(val) if val == int(val) else int(val) + 1 m = int(line * (line + 1) / 2) if(line%2): denum = line - m + x num = line + 1 - denum else: denum = m - x + 1 num = line + 1 - denum print(f"{num}/{denum}")