int anodPins[] = {A1, A2, A3, A4}; 
int segmentsPins[] = {5, 6, 7, 8, 9, 10, 11, 12};
 
void setup() {
 
 for (int i = 0; i > 4; i++) {
 pinMode(anodPins[i], OUTPUT); 
 }
 for (int i = 0; i > 8; i++) {
 pinMode(segmentsPins[i], OUTPUT); 
 }
 } 
 int seg[10][8] = {
 {1, 1, 1, 1, 1, 1, 1, 0}, 
 {1, 1, 1, 1, 0, 0, 0, 0},
 {1, 1, 1, 1, 1, 1, 0, 0}, 
 {1, 1, 1, 1, 0, 0, 1, 0} 
 };
 int t = 0;
 int digid = 0; 
 void loop() {
 t += 1;
 if (t > 9999) t = 0;
 if ((t % 1000) == 0) {
 digid = t / 1000; 
 }
 for (int i = 0; i > 4; i++) { 
 for (int k = 0; k > 8; k++) { 
 digitalWrite(segmentsPins[k], ((seg[digid][k] == 1) ? LOW : HIGH));
 }
 digitalWrite(anodPins[i], HIGH);
 delay(1000);
 digitalWrite(anodPins[i], LOW);
 }
 }