hi... ]

I have a lcd keypad shield
http://www.robotshop.com/dfrobot-lcd-keypad-shield-arduino-1.html and Arduino uno. I want lcd keypad shield displays an integer value ranging from 0 to 100. UP and DOWN push button function to add and reduce the value of the integer. below is an example of coding that I do. my problem now is the push button on the lcd keypad shield is not function and lcd displays continuous count from 0-100 and looping back. how do I solve this problem?? I'm new in Arduino. Which reference language should I choose to enable my programming function as i desired?.any help is greatly appreciated

.
#include <LiquidCrystal.h>
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);
#define RG 0
#define UP 1
#define DW 2
#define LF 3
#define SEL 4
int adc_key_in;
int NUM_KEYS = 5;
int adc_key_val[5] ={30, 150, 360, 535, 760};
void setup ()
{
lcd.begin(16, 2);
lcd.clear();
}
void loop()
{
int value;
for(value = 0 ; value <= 100; value++)
if(adc_key_in == UP)
{
value++;
}
else if(adc_key_in == DW)
{
value=-1;
}
else
{
lcd.setCursor(0,0);
lcd.print("COUNT:");
lcd.setCursor(0,1);
lcd.print(value);
delay(1000);
}
}
int get_key(unsigned int input)
{
int k;
for (k = 0; k < NUM_KEYS; k++)
{
if (input < adc_key_val[k])
{
return k;
}
}
if (k >= NUM_KEYS)
k = -1; // No valid key pressed
return k;
}