Grid Paths II

n,m = map(int, input().split())
if(n==1):
    print(1)
g=[[0 for x in range(n)] for y in range(n)]
for i in range(m):
    y,x=map(int, input().split())
    g[y-1][x-1] = -1
for i in range(n):
    if(g[i][0]<0):
        break
    g[i][0]=1
for i in range(n):
    if(g[0][i]<0):
        break
    g[0][i]=1
for y in range(1,n):
    for x in range(1,n):
        if g[y][x]<0:
            continue
        if g[y-1][x]>-1:
            g[y][x]+=g[y-1][x]
        if g[y][x-1]>-1:
            g[y][x]+=g[y][x-1]
print(g[n-1][n-1]%(10**9 + 7))

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: RUNTIME ERROR

Test 7

Verdict: RUNTIME ERROR

Test 8

Verdict: RUNTIME ERROR

Test 9

Verdict: RUNTIME ERROR

Test 10

Verdict: RUNTIME ERROR