#include <iostream>
#include <cstdio>
#include <queue>
#include <cstring>


using namespace std;

const int N = 1e5 + 10, M = 2e5 + 10;

int e[M], ne[M], h[N], idx;

enum Status {
    WHITE, GRAY, BLACK
};

enum Color {
    RED, BLUE
};


Status status[N];

Color color[N];

void addArc(int x, int y){
    e[idx] = y;
    ne[idx] = h[x];
    h[x] = idx ++;
}

bool bfs(int u){
    queue<int> q;
    q.push(u);
    color[u] = RED;
    status[u] = GRAY;
    while(!q.empty()){
        int v = q.front();
        q.pop();
        Color cur = color[v] == RED ? BLUE : RED;
        for(int i = h[v]; i != -1; i = ne[i]){
            int j = e[i];
            if(status[j] == WHITE){
                status[j] = GRAY;
                q.push(j);
                color[j] = cur;
            }else {
                if(color[j] != cur)return false;
            }
        }
        status[v] = BLACK;
    }

    return true;
}

int main(){
    int n,m,x, y;
    cin >> n >> m;
    memset(h, -1,sizeof h);
    for(int i = 0; i < m; i ++){
        cin >> x >> y;
        addArc(x, y);
        addArc(y, x);
    }

    bool res = true;

    for(int i = 1; i <= n; i ++){
        if(status[i] == WHITE){
            res = res && bfs(i);
            if(!res)break;
        }
    }

    if(res)puts("Yes");
    else puts("No");

    return 0;
}