** Compute the optimal size for the array part of table 't'. 'nums' is a ** "count array" where 'nums[i]' is the number of integers in the table ** between 2^(i - 1) + 1 and 2^i. 'pna' enters with the total number of ** integer keys in the table and leaves with the number of keys that ** will go to the array part; return the optimal size. (The condition ** 'twotoi > 0' in the for loop stops the l
| 345 | ** 'twotoi > 0' in the for loop stops the loop if 'twotoi' overflows.) |
| 346 | */ |
| 347 | static unsigned int computesizes (unsigned int nums[], unsigned int *pna) { |
| 348 | int i; |
| 349 | unsigned int twotoi; /* 2^i (candidate for optimal size) */ |
| 350 | unsigned int a = 0; /* number of elements smaller than 2^i */ |
| 351 | unsigned int na = 0; /* number of elements to go to array part */ |
| 352 | unsigned int optimal = 0; /* optimal size for array part */ |
| 353 | /* loop while keys can fill more than half of total size */ |
| 354 | for (i = 0, twotoi = 1; |
| 355 | twotoi > 0 && *pna > twotoi / 2; |
| 356 | i++, twotoi *= 2) { |
| 357 | a += nums[i]; |
| 358 | if (a > twotoi/2) { /* more than half elements present? */ |
| 359 | optimal = twotoi; /* optimal size (till now) */ |
| 360 | na = a; /* all elements up to 'optimal' will go to array part */ |
| 361 | } |
| 362 | } |
| 363 | lua_assert((optimal == 0 || optimal / 2 < na) && na <= optimal); |
| 364 | *pna = na; |
| 365 | return optimal; |
| 366 | } |
| 367 | |
| 368 | |
| 369 | static int countint (lua_Integer key, unsigned int *nums) { |