1  
 2  contract SafeMath =
 3  
 4    entrypoint add(x, y) = x + y
 5    entrypoint sub(x, y) = x - y
 6    entrypoint mul(x, y) = x * y
 7    entrypoint div(x, y) = x / y
 8    entrypoint rem(x, y) = x mod y
 9    entrypoint pow(x, y) = x ^ y
10