#include <ctime>
#include <iostream>
#include <vector>
// テスト用のmix(この関数は遅いよ!これより早いの作ってね!)
uint32_t mix_test(uint16_t a, uint16_t b) {
uint32_t o = 0;
for (int i = 0; i < 16; i++) {
if (a & (1 << i)) o |= 1 << (i * 2 + 0);
if (b & (1 << i)) o |= 1 << (i * 2 + 1);
}
return o;
}
std::vector<uint32_t> A_MASTER(1<<16, (uint32_t)-1);
std::vector<uint32_t> B_MASTER(1<<16, (uint32_t)-1);
// mixはaとbのbitを交互に詰めて返す。aが下位に来る。
// (例)
// a : 1111111111111111
// b : 0000000000000000
// o : 01010101010101010101010101010101
uint32_t mix(uint16_t a, uint16_t b) {
// ここに実装
uint32_t result_a;
uint32_t result_b;
if (A_MASTER[a] == (uint32_t)-1) {
result_a = 0;
for (int i = 0; i < 16; i++) {
if (a & (1 << i)) {
result_a |= 1 << (i * 2 + 0);
}
}
A_MASTER[a] = result_a;
} else {
result_a = A_MASTER[a];
}
if (B_MASTER[b] == (uint32_t)-1) {
result_b = 0;
for (int i = 0; i < 16; i++) {
if (b & (1 << i)) {
result_b |= 1 << (i * 2 + 1);
}
}
B_MASTER[b] = result_b;
} else {
result_b = B_MASTER[b];
}
return result_a | result_b;
}
// テスト
void test(uint32_t(*func)(uint16_t, uint16_t)) {
std::cout << "test...";
for (int i = 0; i < 100; i++) {
uint16_t a = rand(), b = rand();
if (func(a, b) != mix_test(a, b)) {
std::cout << "failed" << std::endl;
exit(EXIT_FAILURE);
}
}
std::cout << "passed!" << std::endl;
}
// ベンチマーク
void benchmark(uint32_t (*func)(uint16_t, uint16_t)) {
std::cout << "benchmark...";
uint32_t dammy = 0;
double start = clock();
for (int i = 0; i < 50000000; i++) dammy ^= func(rand(), rand());
double end = clock();
std::cout << "end! elapsed:" << (end - start) / CLOCKS_PER_SEC << "s " << dammy << std::endl;
}
int main() {
test(mix);
benchmark(mix);
return 0;
}