Competitive Programmer’s Handbook 笔记

命令行编译：

g++ -std=c++11 -O2 -Wall test.cpp -o test

This command produces a binary file test from the source code test.cpp. The

compiler follows the C++11 standard (-std=c++11), optimizes the code (-O2) and

shows warnings about possible errors (-Wall)

#include<bits/stdc++.h>

using namespace std;

int main()

{

    cout<<INT_MAX<<"\n";

    cout<<LONG_LONG_MAX<<"\n";

    int a = 123456789;

    long long b = a*a;

    cout << b << "\n"; // -1757895751

    b=1LL*a*a;

    cout << b << "\n";

    double x = 0.3*3+0.1;

    printf("%.20f\n", x); // 0.99999999999999988898

    return 0;

}

int  10的9次方，   long long 18次方

long long x = 123456789123456789LL;