字符串比较的耗时远大于数字的比较

下面的例子其实是想展示下，如果一个字符串可以转为数字进行比较，那么还是转成数字吧，这样会快很多，尤其是当比较的次数非常巨大的时候。

#include 
#include 
#include 
using namespace std;
int64_t getCurrentLocalTimeStamp() {
    std::chrono::time_point tp =
        std::chrono::time_point_cast(std::chrono::system_clock::now());
    auto tmp = std::chrono::duration_cast(tp.time_since_epoch());
    return tmp.count();
}

int main()
{
    string a = "111111";
    string b = "600400";
    int64_t start = getCurrentLocalTimeStamp();
    bool flag = false;
    for (int i = 0; i < 10000 * 10000; i++) {
        if (a == b) {
            flag = true;
        }
    }
    int64_t end = getCurrentLocalTimeStamp();
    cout << end - start << "毫秒" << endl;

    start = getCurrentLocalTimeStamp();
    flag = false;
    long along = std::stol(a);
    long blong = std::stol(b);

    for (int i = 0; i < 10000 * 10000; i++) {
        if (along == blong) {
            flag = true;
        }
    }
    end = getCurrentLocalTimeStamp();
    cout << end - start << "毫秒" << endl;
}

运行结果：

1871毫秒
189毫秒