Simple dual counter

counter.ino

#include <TM1637.h>

// pins
int leftPin = 2;
int rightPin = 5;
int resetPin = 8;

// display
int clk = 11;
int dio = 12;
TM1637 TM(clk, dio);

// vars
int leftCount = 0;
int rightCount = 0;
int resetCount = 0;

void setup() {
    TM.init();
    TM.set(2);
    TM.clearDisplay();
    TM.point(1);
    for(int i = 0; i < 4; i++) {
        TM.display(i, 0);
    }

    pinMode(leftPin, INPUT);
    pinMode(rightPin, INPUT);
    pinMode(resetPin, INPUT);
}

void loop() {
    int first = 0;
    int second = 0;
    if (digitalRead(leftPin) == HIGH && leftCount < 99) {
        resetCount = 0;
        leftCount = leftCount + 1;
        first = leftCount / 10;
        second = leftCount % 10;
        TM.display(0, first);
        TM.display(1, second);
        delay(400);
    } else if (digitalRead(rightPin) == HIGH && rightCount < 99) {
        resetCount = 0;
        rightCount = rightCount + 1;
        first = rightCount / 10;
        second = rightCount % 10;
        TM.display(2, first);
        TM.display(3, second);
        delay(400);
    } else if (digitalRead(resetPin) == HIGH) {
        resetCount = resetCount + 1;
        if (resetCount == 3) {
            leftCount = 0;
            rightCount = 0;
            resetCount = 0;
            for(int i = 0; i < 4; i++) {
                TM.display(i, 0);
            }
        }
        delay(400);
    }
}