{

std::cout << "choose selection sort ." << std::endl;

// 每次循环结束，令 [current_loop] 的值为本次循环最小值

for (size_t current_loop = 0; current_loop < num - 1; current_loop++) {

#ifdef DEBUG

std::cout << "-------------- loop time " << current_loop + 1 << " start "

<< "---------------" << std::endl;

show_data(data, num);

#endif

size_t smaller_index = current_loop;

T* target_data = data + current_loop;

T* smaller_data = data + current_loop;

// 每次循环结束，找到本次最小值，记录在 smaller_data 中

for (size_t current_index = current_loop + 1; current_index < num - 1; current_index++) {

T* loop_data = data + current_index;

if (*loop_data < *smaller_data) {

smaller_data = loop_data;

}

}

#ifdef DEBUG

std::cout << "target data : " << *target_data << std::endl;

std::cout << "smaller data : " << *smaller_data << std::endl;

#endif

// target_data <==> smaller_data

T temp = *target_data;

*target_data = *smaller_data;

*smaller_data = temp;

#ifdef DEBUG

std::cout << "-------------- loop time " << current_loop + 1 << " result "

<< "--------------" << std::endl;

show_data(data, num);

std::cout << "-------------- loop time " << current_loop + 1 << " end "

<< "-----------------" << std::endl << std::endl;

#endif

}

}