cleanups

d02.cc

@@ -8,9 +8,9 @@ vector<array<unsigned, 2>> parse()
 {
     vector<array<unsigned, 2>> input;
     for (string line; getline(cin, line);) {
-        if (line.size() < 3 || line[1] != ' ') throw "parse";
+        if (line.at(1) != ' ') throw "parse";
-        unsigned oppo = line[0] - 'A';
+        unsigned oppo = line.at(0) - 'A';
-        unsigned user = line[2] - 'X';
+        unsigned user = line.at(2) - 'X';
         if (oppo >= 3 || user >= 3) throw "parse";
         input.push_back({oppo, user});
     }