# Can you find some relation

#### dhairya bhardwaj

hey everyone , I am writing a computer program but I am stuck somewhere
If you can find any logic or relation between the following data so I can handle of them in one single statement ?

i j

1 2
2 5
3 3
4 1
5 4

#### romsek

Math Team
Even if there is some arcane input output relationship between these two arrays it's fairly poor programming to try and force some sort of mathematical formula to describe it. With hardware resources being a mostly insignificant concern these days clarity is a more important property of good code.

j = switch {
case 1 : 2;
case 2 : 5;
case 3 : 3;
case 4 : 1;
case 5 : 4;
default : printf(stderr, "Undefined input\n");
}

or a more typical way of doing this is with an array.

int f = {2,5,3,1,4};

j = f[i+1];

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#### fysmat

If one really wish to write a formula for it, maybe $$\displaystyle j = \frac{5}{6}i^3 - 7\tfrac{1}{2}i^2 + 19\tfrac{2}{3}i - 11$$ works.

#### abdallahhammam

2+3*(i-1)-5/20*(i-1)(i-2)+5/6*(i-1)(i-2)(i-3).
we use finite differences of Newton method of polynomial interpolation.