import
java.util.*;
public
class
CountString {
static
long
mod =
1000000007
;
static
long
binpow(
long
a,
long
b) {
long
ans =
1
;
while
(b >
0
) {
if
(b %
2
==
1
) {
ans = (ans * a) % mod;
}
a = (a * a) % mod;
b /=
2
;
}
return
ans;
}
static
long
ncr(
long
a,
long
b) {
long
facta =
1
;
long
factb =
1
;
long
factab =
1
;
for
(
long
i = a; i >=
1
; i--) {
facta = (facta * i) % mod;
}
for
(
long
j = b; j >=
1
; j--) {
factb = (factb * j) % mod;
}
long
x = a - b;
for
(
long
i = x; i >=
1
; i--) {
factab = (factab * i) % mod;
}
long
invab = binpow(factab, mod -
2
);
long
invb = binpow(factb, mod -
2
);
long
answer = (facta * invb) % mod;
answer = (answer * invab) % mod;
return
answer;
}
static
int
countString(
int
x,
int
y) {
long
rem = y - x +
1
;
if
(rem <
0
) {
return
0
;
}
long
answer = ncr(y +
1
, x);
return
(
int
) answer;
}
public
static
void
main(String[] args) {
int
x =
2
;
int
y =
2
;
System.out.println(countString(x, y));
}
}