$6]$ Whats the error in the following program?

int i;

union uuu $\{$

unsigned un;i

nt in;

float fl;

$\}$;

union uuu arr$[3]$;$//$array of $3$ union elements

arr$[0].$un $=42$;

arr$[1].$in $=-42$;

arr$[2].$fl $=42\mathrm{.}0$f;

for $($i$=0$;i$<mn>3</mn>$;i$++)$

printf$("$arr$[\%$d$]=$ d$",$ arr$[$i$].$un$)$;

Solve for code blocks not C$++$