#include <bits/stdc++.h>
using namespace std;
ifstream fin("strmatch.in");
ofstream fout("strmatch.out");
char s1[2000009],s2[2000009];
int prefix[2000009],ans[1009],k;
void pre()
{
    int i=1,j=0;
    while(i<strlen(s1))
    {
        while(s1[i]==s1[j]&&i<strlen(s1))
            prefix[i++]=j+1,j++;
        while(s1[j]!=s1[i]&&j!=0)
            j=prefix[j-1];
        i++;
    }

}
int main()
{
    cin>>s1>>s2;
    pre();
    int j=0;
    for(int i=0;i<strlen(s2);i++)
    {
        while(s1[j]!=s2[i]&&j!=0)
                j=prefix[j-1];
        if(s1[j]==s2[i])
            j++;
        if(j==strlen(s1))
        {
            if(k<1000)
                ans[++k]=i-j+1;
        }
    }
    cout<<k<<'\n';
    for(int i=1;i<=min(1000,k);i++)
        cout<<ans[i];
}