C++初学者真诚求高手指点，万谢万谢！

请看一下程序：
#include "stdafx.h"
#include <iostream>
#include<fstream>
#include<vector>
#include<cmath>
using namespace std;
class MVector
{
  // storage for the new vector class
  std::vector<double> v;
  public:
    // constructor
    explicit MVector(){};
    explicit MVector(int n):v(n){};
    explicit MVector(int n,double x):v(n,x){};
    // destructor
    ~MVector(){};
    // equate vectors;
    MVector& operator=(const MVector& X)
    {if(&X==this)return *this;v=X.v;return *this;};
    // access data in vector
    double& operator[](int index){return v[index];};
    // access data in vector (const)
    double operator[](int index) const {return v[index];};
    // size of vector
    int size() const {return v.size();};
 void push_back(double x){v.push_back(x);}
}; // end class MVector

    void runningaverage(const MVector &v,int m,int p)
 {
      MVector runningaverage(v.size()-m-p);
 cout << " runningaverage:= ( ";

   for(int i=0;i<=runningaverage.size();i++)
   {
    double sum=0.;
    for(int j=i;j<=i+m+p;j++){sum+=v[j];}
    runningaverage[i]=sum/(m+p+1);
    cout << runningaverage[i] << " " ;
   }
cout << ")\n";

 }
   
int main(int argc, char** argv)
{
 MVector x;
    x.push_back(1.2);
 x.push_back(2.1);
 x.push_back(1.9);
    x.push_back(3.4);
 x.push_back(3.9);
 x.push_back(2.7);
 x.push_back(1.6);
 x.push_back(2.3);
 x.push_back(2.4);
 cout << " x:= ( ";
 for (int i=0;i<x.size();i++)
  cout << x[i] << "  ";
 cout << ")\n";
 runningaverage(x,2,1);
}
先说下我想求一个数列的移动平均数runningaverage，其定义见附件的图。
之前都是好好，Class MVector的部分是照搬老师的，完全没有问题，问题出现在加了runningaverage函数以后，所以你仔细看看runningaverage的循环。结果是能运行出来的，就是跳出俩窗口说
1、Expression:vector subscript out of range.
2、Expression:("Standard C++ libraries out of range",0)
为什么会这样呢？不明白。求解答。
万谢万谢！！