#include <stdio.h>
int Hermite(int n, int x) {
int ret = 0;
if (n == 0) {
ret = 1;
} else if (n == 1) {
ret = 2 * n;
} else if (n > 1) {
ret = 2 * x * Hermite(n - 1, x) - 2 * (n - 1) * Hermite(n - 2, x);
}
return ret;
}
int main() {
int n, x = 0;
scanf("%d %d", &n, &x);
printf("%d", Hermite(n, x));
return 0;
}

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