How to iterate over an array of tuples? : So I'm new at learning rust and we're doing a poker assignment in which a base of 2 hands is given as such:

        let hand1 = [(3, 'H'), (10, 'S'), (4, 'S'), (4, 'C'), (5, 'C')];
        let hand2 = [(2, 'H'), (2, 'S'), (5, 'S'), (2, 'C'), (13, 'C')];
        let xxx = highest_card(&hand1, &hand2);

My first goal with this is to figure out in each hand what the highest card is. What I've tried to is pass in the reference to each array to another function, that is suppose to figure it out. 

    fn highest_card(c: &[(i32, char)] , d: &[(i32, char)])
    {

      let mut max = 0;
      let mut m : usize = 0;
      let n: usize = 0;

      while m < c.len()
        {
          if c[m].n > max
           {
             max = c[m].n;
           }
          m += 1;
        }
        println!("The max number is: {}", max);
    }

But when running this it displays the error:
       [Picture of terminal displaying errors, stack overflow doesn't yet let me embed pics to my post because of < 10 exp][1]


  [1]: https://i.stack.imgur.com/oJjZg.png

What should I do to address this issue?