//{{{ #include using namespace std; #define rep(...) repN((__VA_ARGS__,rep3,rep2,loop,~))(__VA_ARGS__) #define loop(n) rep2(_loop_,n) #define rep2(i,n) rep3(i,0,n) #define rep3(i,begin,end) for(int i=(int)(begin),i##_end=(int)(end);i> W >> D; rep(i, D - 1){ W -= W / (D - i) / (D - i); } printf("%d\n", W); return 0; }