c++ primer 阅读 day8

3.4 迭代器介绍

#include<iostream>

using namespace std;

int main()
{
    string s("some string");
    if(s.begin() != s.end()){
        auto it = s.begin();
        *it = toupper(*it);
    }

    cout<<s<<endl;

    for(auto it =s.begin(); it!=s.end() && !isspace(*it);++it)
        *it = toupper(*it);
     cout<<s<<endl;

      for(auto it = s.cbegin(); it!=s.cend(); ++it)
        cout<<*it;

     string text;
     while(cin>>text)

     for(auto it = text.begin(); it!=text.end(); ++it)
        cout<<*it;
    return 0;
}

使用迭代器运算
二分查找

#include<iostream>
#include<vector>
using namespace std;

int main()
{
    cout<<"input increase number: ";
    vector<int> iVec(0);
    int iNum = 0;
    while(cin>>iNum && iVec.size()<6)
        iVec.push_back(iNum);
    auto low = iVec.begin(), high = iVec.end();
    auto mid = iVec.begin() + (high -low)/2;

    int sought = 0;
    cout<<"input you want find number: ";
    cin>>sought;
    while(mid != high && *mid != sought )
    {
        if(sought < *mid)
            high = mid;   //忽略后半部分
        else
            low = mid + 1;
        mid = low + (high - low)/2;
    }
    cout<<*mid<<endl;
    return 0;
}

3.5 数组