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guyueshui · Nov 7, 2018 · 83dde5a · 83dde5a
1 parent 71e4cbc
commit 83dde5a
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/Gp2_1.cpp b/Gp2_1.cpp
@@ -39,11 +39,14 @@ vector<int> merge(vector<int>& a, vector<int>& b){
 vector<int> mergesort(vector<int>& seq){
 	if (seq.size() == 1) return seq;
 	else{
+		// split the seq into two subseqs
 		int lsize = seq.size() >> 1;
 		int rsize = seq.size() - lsize;
 		vector<int> tmpl, tmpr, lseq, rseq;
 		tmpl.assign(seq.begin(), seq.begin()+lsize);
 		tmpr.assign(seq.end()-rsize, seq.end());
+
+		// recursively slove subproblems 
 		lseq = mergesort(tmpl);
 		rseq = mergesort(tmpr);