hdu6114 2017"百度之星"初赛(B)1001Chess(dp)

#include <bits/stdc++.h>
#define mod 1000000007
#define ll long long
#define N 1005
int n,m,tst,f

;
inline int read(){
int x=0,f=1;char ch=getchar();
while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while(ch>='0'&&ch<='9') x=x*10+ch-'0',ch=getchar();
return x*f;
}
int main(){
//  freopen("a.in","r",stdin);
tst=read();
for(int i=1;i<=1000;++i) f[1][i]=i,f[i][i]=1;
for(int i=2;i<=1000;++i)
for(int j=i+1;j<=1000;++j)
f[i][j]=(f[i][j-1]+f[i-1][j-1])%mod;
while(tst--){
n=read();m=read();if(n>m) std::swap(n,m);
printf("%d\n",f
[m]);
}
return 0;
}