编写一个函数，接受三个string参数，s，oldVal和newVal。使用迭代器及insert和erase函数将s中所有oldVal替换为newVal。测试你的程序，用他替换通用的简写形式，如，将“tho”，将“”“”

// test14.cpp : 定义控制台应用程序的入口点。
//

include "stdafx.h"

include

include

include

include

include

include

include <initializer_list>

include

include

using namespace std;
class Solation
{
public:
string fun(string &s,string oldVal,string newVal)
{
string:size_t pos = 0;
while (pos<s.length())
{
pos = s.find(oldVal, pos);//从零号位置开始查找
if (pos >= s.length()) break;//如果没有找到退出循环

s.erase(pos,oldVal.length());//如果找到，先删除原来的字符
s.insert(pos,newVal);//添加新的字符

//s.replace(pos,oldVal.length(),newVal);//和上面两句是等价的

pos = pos + newVal.length();//移动pos位置
}
cout << s<< endl;
return s;
}

};

int main()
{
string s = "WangDanPiaoLiang!";
string oldVal = "Dan";
string newVal = "dandan";

Solation so;
//so.fun(s,oldVal,newVal);

cout << endl;

string str = so.fun(s, oldVal, newVal);

cout << str<< endl;
return 0;
}