Add built-in answer tones and automatic multiple-choice progression

quiz.h

@@ -0,0 +1,19 @@
+#ifndef QUIZ_H
+#define QUIZ_H
+#define STATE_COUNT 50
+#define ANSWER_SIZE 40
+typedef unsigned char U8;
+typedef struct { const char *code; const char *name; const char *capital; } State;
+extern const State states[50];
+extern U8 order[50], options[4], question, score, corrections;
+extern U8 answered[50], correct[50], corrected[50];
+extern char responses[50][ANSWER_SIZE];
+extern unsigned random_state;
+void quiz_start(unsigned seed);
+unsigned quiz_random(unsigned bound);
+void quiz_options(U8 state);
+void normalize(const char *in, char *out);
+/* 2 exact/alias, 1 near, 0 wrong (including a different known capital). */
+U8 classify(U8 state, const char *answer);
+void quiz_record(U8 state, const char *answer, U8 right, U8 spelling);
+#endif