You are given two strings $S$ and $T$, each of length $\alpha$, consisting only of lower case English letters $(a,b, \dots ,z)$. Propose an $O(\alpha)$-time algorithm to decide whether $S$ can be obtained by permuting the symbols of $T$. For example, if $S \: = \: \text{ algorithm}$, $T \: = \text{ logarithm}$, your algorithm should return $\text{YES}$; but if $S \: = \text{ trainee}$, $T\: = \text{ retinaa}$, your algorithm should return $\text{NO}$.