Number_of_Unique_path

int NumberOfPath(int a, int b)
    {
        int arr[a+1][b+1];
        for(int i=0;i<=a;i++)
        {
            for(int j=0;j<=b;j++)
            {
                if(i==0 || j==0)
                arr[i][j]=0;
                else if(i==1 || j==1)
                arr[i][j]=1;
                else
                arr[i][j]=arr[i][j-1]+arr[i-1][j];
            }
        }
        return arr[a][b];
    }