#include <iostream> using namespace std; int len = 1; int a[1005][1005]; void add(int x) { for(int i = 1;i <= len;i++) a[x][i] = a[x - 1][i] + a[x - 2][i]; for(int i = 1;i <= len;i++) if(a[x][i] > 9) { a[x][i + 1] += a[x][i] / 10; a[x][i] %= 10; } if(a[x][len + 1]) len++; } int main () { int n , m; cin >> n >> m; a[1][1] = 1; a[2][1] = 2; for(int i = 3;i <= m - n;i++) add(i); for(int i = len;i >= 1;i--) cout << a[m - n][i]; return 0; }