keypress.c

keypress.c

#include "string.h"
#include "stdlib.h"
#include "stdio.h"

int NUM_KEYS = 9; // 2 - 9 and 0

struct Number {
	int number; // number on keypad
	char *letters; // letters associated with number
	int hits; // number of times pressed
};

struct Number keypad[] = {
	{ 0, " ", -1 },
	{ 2, "abc", -1 },
	{ 3, "def", -1 },
	{ 4, "ghi", -1 },
	{ 5, "jkl", -1 },
	{ 6, "mno", -1 },
	{ 7, "pqrs", -1 },
	{ 8, "tuv", -1 },
	{ 9, "wxyz", -1 }
};

void pressKey(int key) {
	keypad[key].hits += 1;
}

int main(int argc, char *args[]) {
	args++; // skip first argument
	int previousKey = -1;
	while(*args) {
		int key = atoi(*args);
		if (key != 0) {
			key -= 1;
		}

		if (previousKey == -1) {
			previousKey = key;
		} else if (previousKey != key) {
			int letterToPrint = keypad[previousKey].hits % strlen(keypad[previousKey].letters);
			printf("%c", keypad[previousKey].letters[letterToPrint]);
			keypad[previousKey].hits = -1;
		} else if (keypad[previousKey].hits == strlen(keypad[previousKey].letters) - 1) {
			int letterToPrint = keypad[previousKey].hits;
			printf("%c", keypad[previousKey].letters[letterToPrint]);
			keypad[previousKey].hits = -1;
		}
		pressKey(key);
		previousKey = key;
		args++;
	}
	printf("\n");
}