#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
const int N = 100010, M = 200010;
int n,m,h[N],e[M],ne[M],idx,color[N];
void add(int a,int b)
{
    e[idx]=b,ne[idx]=h[a],h[a]=idx++;
}
bool dfs(int u,int c)
{
    color[u]=c;
    int i,j;
    for(i=h[u];i!=-1;i=ne[i]){
        j=e[i];
        if(!color[j]){
            if(!dfs(j,3-c))return false;
        }
        else if(color[j]==c)return false;
    }
    return true;
}
int main()
{
    scanf("%d%d",&n,&m);
    memset(h,-1,sizeof h);
    int a,b,i;
    bool flag=true;
    while(m--){
        scanf("%d%d",&a,&b);
        add(a,b),add(b,a);
    }
    for(i=1;i<=n;i++)
        if(!color[i]){
            if(!dfs(i,1)){
                flag=false;
                break;
            }
        }
    if(flag)printf("Yes\n");
    else printf("No\n");
    return 0;
}