#include using namespace std; #define INF 1e9+7 int mod(int a, int b){ int r = a % b; return (r>0) ? r : r + b; } int main(){ int N,S,K; vector> dp; cin >> N >> S >> K; for(int i=0; i(S+1,0)); dp.at(0).at(0) = 1; for(int i=0; i=0) dp.at(i+1).at(j) = dp.at(i).at(j) + dp.at(i+1).at(j-N+i); else dp.at(i+1).at(j) = dp.at(i).at(j); dp.at(i+1).at(j) = mod(dp.at(i+1).at(j), INF); } } cout << dp.at(N).at(S) << endl; return 0; }