#include<bits/stdc++.h>
#define fr(i,j,k) for(register int i=j;i<=k;++i)
#define rf(i,j,k) for(register int i=j;i>=k;--i)
#define foredge(i,j) for(register int i=head[j];i;i=e[i].nxt)
#define pb push_back
#define Times printf("Time:%.3lf\n",clock()/CLOCKS_PER_SEC)
using namespace std;
inline int read(){
	int x=0;
	bool f=0;
	char c=getchar();
	while(!isdigit(c)) f|=(c=='-'),c=getchar();
	while(isdigit(c)) x=(x<<3)+(x<<1)+(c^48),c=getchar();
	return f?-x:x;
}
inline void write(int x){
    if(x<0){putchar('-');x=-x;}
    if(x>9)write(x/10);
    putchar(x%10+'0');
}
inline void writeln(int x){write(x); puts("");}
inline void writepl(int x){write(x); putchar(' ');}
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
inline int randfind(int l,int r){return rnd()%(r-l+1)+l;}
//inline void init(){
//	int t=read();
//	while(t--) work();
//}
const int mod=1e9+7;
inline int ksm(int x,int y){
    int sum=1;
    while(y){
        if(y&1) sum=1ll*sum*x%mod;
        y=y/2;x=1ll*x*x%mod;
    }
    return sum;
}
int ans;
const int Maxn=1e6+10;
char c[Maxn];
inline void work(){
    ans=0;
    int n=strlen(c+1);
    if(n&1){
        if(n==1){
            if(c[1]=='1') puts("1");
            else puts("0");
            return;
        }
        int num=0;
        fr(i,2,n-1) num+=(c[i]=='?');
        if(c[1]==c[n] && c[1]!='?'){
            puts("0");
            return;
        }
        if(c[1]!='?' && c[n]!='?'){
            writeln(ksm(2,num));
            return;
        }
        num+=(c[1]=='?');num+=(c[n]=='?');--num;
        writeln(ksm(2,num));
        return;
    }
    int num=0;
    fr(i,1,n) num+=(c[i]=='?');
    if(num==0){
        fr(i,1,n) num^=(c[i]-'0');
        writeln(num);
        return;
    }
    writeln(ksm(2,num-1));
}
inline void init(){
    while(scanf("%s",c+1)!=EOF) work();
}
signed main(){
	// freopen("input.in","r",stdin);
	// freopen("output.out","w",stdout);
    init();
    // printf("\nTIME:%.3lf",(double)clock()/CLOCKS_PER_SEC);
	return 0;
}