Index: lib/numeric/modArith.cpp
==================================================================
--- lib/numeric/modArith.cpp
+++ lib/numeric/modArith.cpp
@@ -26,24 +26,20 @@
 mint operator*(mint x, mint y) { return x*=y; }
 mint operator/(mint x, mint y) { return x/=y; }
 vector<mint> FAC_(1,1);
 mint FAC(LL n) { while( FAC_.size()<=n ) FAC_.push_back( FAC_.back()*FAC_.size() ); return FAC_[n]; }
 mint C(LL n, LL k) { return k<0 || n<k ? 0 : FAC(n) / (FAC(k) * FAC(n-k)); }
-
-// Pascal's triangle: if O(1) nCk is needed.
-vector< vector<mint> > CP_(2001);
+vector< vector<mint> > CP_; // Pascal's triangle: if O(1) nCk is needed.
 mint C(LL n, LL k) {
-	if(CP_[0].empty()) {
-		CP_[0].push_back(1);
-		for(int nn=1; nn<CP_.size(); ++nn)
-		for(int kk=0; kk<=nn; ++kk)
-			CP_[nn].push_back( (kk?CP_[nn-1][kk-1]:0) + (kk<nn?CP_[nn-1][kk]:0) );
+	while( CP_.size() <= n ) {
+		int nn = CP_.size();
+		CP_.push_back(vector<mint>(nn+1,1));
+		for(int kk=1; kk<nn; ++kk)
+			CP_[nn][kk] = CP_[nn-1][kk-1] + CP_[nn-1][kk];
 	}
 	return k<0 || n<k ? 0 : CP_[n][k];
 }
-
-
 
 /*
 // MODVAL must be a prime!!
 LL GSS(LL k, LL b, LL e) // k^b + k^b+1 + ... + k^e
 {