include

include

char s[100005]; int arr[100005][3];

int fun(int x,int m){

if(x>=strlen(s))
return 0;
else if(arr[x][m]!=-1)
return arr[x][m];
else {
     if((s[x]-'0'+m)%3==0 && (s[x]-'0')%2==0){
    arr[x][m]=fun(x+1,(s[x]-'0'+m)%3)+1;
}
    else {
    arr[x][m]=fun(x+1,(s[x]-'0'+m)%3); }
    return arr[x][m];
}

}

int main(){ scanf(" %s",s); int j,i=0; long long ans=0; for(j=0;j<100005;j++){ arr[j][0]=arr[j][1]=arr[j][2]=-1;} while(s[i]!='\0'){ if((int)s[i]=='0'){

  ans=ans+1;
  }
else {
    ans=ans+fun(i,0);

    }

        i++;}
    printf("%lld",ans);

return 0;}
//can anyone please help out.
//my above code is giving time out for test cases above 12