Reading the Mann–Whitney $U$ statistic off a fully specified combined ranking

X and Y are two continuous random variables independent of each other. The combined sample based on two independent samples of size 5 and 4 on X and Y respectively has the following pattern: $y_4<x_1<x_5<y_3<x_2<y_1<y_2<x_4<x_3$. Hence the value of Mann-Whitney-Wilcoxon test statistic is: