#include <iostream>
#include <algorithm>
#include <cstring>
using namespace std;

const int N = 100010, M = 200010;
int e[M], ne[M], h[N], idx;
int n, m;
int color[N]; //染色数组 0,1,2   

void add(int a, int b){
    e[++ idx] = b, ne[idx] = h[a], h[a] = idx;
}

bool dfs(int x, int c){ //给x染色  
    color[x] = c;     
    for(int i = h[x]; i; i = ne[i]){    
        int y = e[i];
        if(!color[y] && !dfs(y, 3 - c))
            return false; 
        else if(color[y] == c) //奇数环 
            return false; 
    }
    return true;
}

int main(){
    cin >> n >> m;
    while (m --){
        int a, b;
        scanf("%d%d", &a, &b);
        add(a, b), add(b,a);
    }

    bool flag = true;
    for (int i = 1; i <= n; i ++) //可能不连通    
        if(!color[i] && !dfs(i, 1)){ 
            flag = false;
            break;
        }

    if(flag) puts("Yes");
    else puts("No");
    return 0;
}