Crying Child

There are **n** stars in the night sky and a child wishes to see minimum **m** stars. If there are less than **m** stars in the sky the child cries. Each minute number of star increases in the sky by 1. After how many minutes will the child stop crying. ### Input - First line of input conatins number of test cases **T**. - Next **T** lines contain two integers **n** and **m** denoting the number