C++ map用法

int main()
{
	void *p;
	str *st;
	st = (str*)malloc(sizeof(str));
	st->a = 23;
	st->b = 24;
	p = st;
	//使用void指针需强制类型转换
	printf("%d\n%d\n",((str*)p)->a, ((str*)p)->b);
	free(st);

	map<char, int> mpci;
	mpci['m'] = 20;
	mpci.insert(pair<char, int>('r', 30));//插入元素
	mpci.insert(pair<char,int>('a',40));
	map<char, int>::iterator iterci;
	for(iterci = mpci.begin(); iterci != mpci.end(); iterci++)
		printf("%c:%d ", iterci->first, iterci->second);//已自动排序
	printf("\n");
	iterci = mpci.find('r');//查找元素
	printf("Erase %c:%d\n",iterci->first,iterci->second);
	mpci.erase(iterci);
	printf("Erase %c:%d\n", 'a', mpci['a']);
	mpci.erase('a');
	if (!mpci.count('a'))//查找有无
		printf("'a' NULL\n");
	for (iterci = mpci.begin(); iterci != mpci.end(); iterci++)
		printf("%c:%d ", iterci->first, iterci->second);//已排序
	printf("\n");
	printf("At %c:%d \n", 'm', mpci.at('m'));//取出键对应的值


    std::cout << "Hello World!\n";
}