$(10$ points$)$ Consider an array composed of unique numbers. The objective is to identify

all ordered pairs $(x,y)$ within this array where the remainder of the division of the

first number $($x$)$ by the second number $($y$)$ equals a specified integer, $r.$

Example $1$:$-$ arr$[]=\{4,5,2,1,3\}$ and $r=2,$ the output should be $(2,3),(2,5),(5,3),(2,4).$

Example $2$:$-$ arr$[]=\{6,1,4,10,9\}$ and $r=2.$ The output is the set of pairs

$(6,4),(10,4)$

The length of the array $n$ is such that $1n{10}^6.$

and range of $r1k{10}^6.$