FriendSet

/*
    Task    : _example
    Author  : Phumipat C. [MAGCARI]
    Language: C++
    Created : 26 February 2023 [11:53]
*/
#include<bits/stdc++.h>
#define rep(i, a, b) for(int i = a; i <= (b); ++i)
#define repr(i, a, b) for(int i = a; i >= (b); --i)
#define repl(i, a, b) for(LL i = a; i <= (b); ++i)
#define reprl(i, a, b) for(LL i = a; i >= (b); --i)
#define all(x) begin(x),end(x)
#define allst(x,y) (x).begin()+y,(x).end()
#define rmdup(x) sort(all(x)),(x).resize(unique((x).begin(),(x).end())-(x).begin())
#define sz(x) (int)(x).size()
#define decp(x) fixed << setprecision(x)
#define MOD (LL )(1e9+7)
using namespace std;
using LL = long long;
using PII = pair<int ,int >;
using PLL = pair<long long ,long long >;
const int dir4[2][4] = {{1,-1,0,0},{0,0,1,-1}};
const int dir8[2][8] = {{-1,-1,-1,0,1,1,1,0},{-1,0,1,1,-1,0,1,-1}};
map<vector<int >,int > case1,case2;
vector<int > friendList[100010];
int main(){
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);
    int n,m;
    cin >> n >> m;
    for(int i=1;i<=m;i++){
        int x,y;
        cin >> x >> y;
        friendList[x].push_back(y);
        friendList[y].push_back(x);
    }
    int ans = 0;
    for(int i=1;i<=n;i++){
        sort(friendList[i].begin(),friendList[i].end());
        ans+=case1[friendList[i]];
        case1[friendList[i]]++;

        friendList[i].push_back(i);
        sort(friendList[i].begin(),friendList[i].end());
        ans+=case2[friendList[i]];
        case2[friendList[i]]++;
    }
    cout << ans << '\n';
    return 0;
}