1577
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <math.h>
#include <limits.h>
#include <hash_map>
 
using namespace std;
//using namespace stdext;
 
// Datatypes
typedef vector<int> vi; 
typedef vector<string> vs;
typedef vector<vi> vvi; 
typedef pair<int,int> ii; 
typedef long long ll;
typedef long double ld;
 
// Define
#define sz(a)             int((a).size()) 
#define pb                push_back 
#define all(c)            (c).begin(),(c).end() 
#define present(c,x)      ((c).find(x) != (c).end()) 
#define cpresent(c,x)     (find(all(c),x) != (c).end()) 
#define FOR(_i,_n)        for(int (_i) = 0; (_i) < (_n); (_i)++)
#define mp                make_pair
 
// Constants
const double eps = 1e-8; 
const double PI = 3.1415926535897932384626433832795;
 
#define INPUT_FILE "feelgood.in"
#define OUTPUT_FILE "feelgood.out"
 
unsigned int m[2010][2010] = {0};
unsigned int r[2010][2010] = {0};
unsigned int mod = 1000000007;
char s1[3000];
char s2[3000];
 
int main(void)
{
#ifdef ALEX
    freopen("input.in", "r", stdin);
    freopen("output.out", "w", stdout);
#else
    //freopen(INPUT_FILE, "r", stdin);
    //freopen(OUTPUT_FILE, "w", stdout);
#endif
 
    scanf("%s", s1);
    scanf("%s", s2);
 
    int l1 = strlen(s1);
    int l2 = strlen(s2);
 
    for(int i = 0; i < 2010; i++)
    {
        r[0][i] = 1;
        r[i][0] = 1;
    }
 
    for(int i = 0; i < l1; i++)
    {
        for(int j = 0; j < l2; j++)
        {
            int ii = i+1;
            int jj = j+1;
            if(s1[i] == s2[j])
            {
                m[ii][jj] = m[ii-1][jj-1] + 1;
            }
            else
            {
                m[ii][jj] = max(m[ii-1][jj], m[ii][jj-1]);
            }
 
            if(s1[i] == s2[j])
                r[ii][jj] = r[ii-1][jj-1];
            else
            {
                if(m[ii-1][jj] == m[ii][jj]) 
                    r[ii][jj] = ((r[ii][jj] % mod) + (r[ii-1][jj] % mod)) % mod;
 
                if(m[ii][jj-1] == m[ii][jj]) 
                    r[ii][jj] = ((r[ii][jj] % mod) + (r[ii][jj-1] % mod)) % mod;
            }
        }
    }
 
    cout << r[l1][l2];
 
    return 0;
}
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