#include uint64_t __rand48_step(unsigned short *xi, unsigned short *lc) { uint64_t a, x; x = xi[0] | xi[1]+0U<<16 | xi[2]+0ULL<<32; a = lc[0] | lc[1]+0U<<16 | lc[2]+0ULL<<32; x = a*x + lc[3]; xi[0] = x; xi[1] = x>>16; xi[2] = x>>32; return x & 0xffffffffffffull; }