Reading Pin data

I have a dtmf module which i want to hook up with a UNO it gives 4 pin output how wud i read this with an arduino

Connect the four output pins to four input pins on the Arduino. Read the pins with digitalRead() to get a 1 or 0 for each.

const int InputBit0Pin = 4;
const int InputBit1Pin = 5;
const int InputBit2Pin = 6;
const int InputBit3Pin = 7;

void loop() {
    int input = (digitalRead(InputBit3Pin) << 3) | (digitalRead(InputBit2Pin) << 2) | (digitalRead(InputBit1Pin) << 1) | digitalRead(InputBit0Pin); 

}