我进行pop_back操作时，出现运行时错误，我晓不得咋个改，但晓得是pop_back出问题，帮我看一下



#include <iostream>
#include <deque>
#include <algorithm>
#include <iterator>
#include <time.h>
using namespace std;
enum{SIZE=20};
int main()
{
    srand(time(0));
    int arr[SIZE];
    for (int i = 0; i < SIZE;i++)
    {
        arr[i] = rand()%100;
    }
    deque<int>pm;
    pm.insert(pm.begin(), arr, arr + SIZE);
    for (deque<int>::iterator p = pm.begin(); p != pm.end();p++)
    {
        cout << "pm:" << *p << endl;
        
    }
    /*
    pm.push_back(1);
    pm.push_back(1);
    pm.push_back(1);
    pm.push_back(1);
    pm.push_back(1);
    pm.push_back(1);
    */
    sort(pm.begin(), pm.end());
   
    for (int i = 0; i < SIZE;i++)
    {
        cout << "pm["<<i<<"]:" << pm[i] << endl;
    }
    //pm.pop_back();
    pm.pop_back();
    for (int i = 0; i < SIZE; i++)
    {
        cout << "pm[" << i << "]:" << pm[i] << endl;
    }
    while (1);
    return 0;
}

谢谢你们了