// luogu-judger-enable-o2

# include<iostream>

# include<cmath>

# include<algorithm>

# include<cstdio>

const int rqy = ;

const int mn = ;

char a[mn],b[mn];

int f[][mn][mn];

inline void cal(int &a,int &b)

{

    a=a+b;

    if(a>=rqy)

        a-=rqy;

}

int n,m;

int main()

{

    scanf("%d%d",&n,&m);

    scanf("%s",a+);

    scanf("%s",b+);

    int cur=;

    f[][][]=;

    for(int i=;i<=n;i++,cur^=)

        for(int j=;j<=m;j++)

          for(int k=;k<=n;k++)

    {

       if(i+j-k>m || i+j-k<) continue;

       if(a[i+]==a[k+])

        cal(f[cur^][j][k+],f[cur][j][k]);

       if(a[i+]==b[i+j-k+])

        cal(f[cur^][j][k],f[cur][j][k]);

       if(b[j+]==b[i+j-k+])

        cal(f[cur][j+][k],f[cur][j][k]);

       if(b[j+]==a[k+])

        cal(f[cur][j+][k+],f[cur][j][k]);

       f[cur][j][k]=;

    }

    printf("%d",f[cur][m][n]);

    return ;

}