internal void init_block()
{
// Initialize the trees.
for (int i = 0; i < L_CODES; i++)
dyn_ltree[i * 2] = 0;
for (int i = 0; i < D_CODES; i++)
dyn_dtree[i * 2] = 0;
for (int i = 0; i < BL_CODES; i++)
bl_tree[i * 2] = 0;
dyn_ltree[END_BLOCK * 2] = 1;
opt_len = static_len = 0;
last_lit = matches = 0;
}