Text Input arduino (directional buttons) 5 buttons

#include <LiquidCrystal.h>
LiquidCrystal lcd(7,6,5,4,3,2);
int i=0;
char input[] = "a";
const int dw = 8;
const int ri = 9;
const int le = 10;
const int up = 11;
const int ok = 12;
const int mn = 13;

int bdw=0, bri=0, ble=0, beu=0, beo=0, bem=0;

void setup()
{
  pinMode(dw, INPUT);
  pinMode(ri, INPUT);
  pinMode(le, INPUT);
  pinMode(up, INPUT);
  pinMode(ok, INPUT);
  pinMode(mn, INPUT);
}
void intext()
{
  int lim=16;
  lcd.setCursor(0,1);
  lcd.print(input);
  for(i=0; i<lim ; )
  {
    lcd.setCursor(0,1);
    lcd.print(input);
    if(digitalRead(dw)==HIGH)
    {
      if(input[i]>'z')
        input[i]='a';
      input[i]=input[i]+1;
      delay(500);
    }
    if(digitalRead(up)==HIGH)
    {
      if(input[i]<'a')
        input[i]='z';
      input[i]=input[i]-1;
      delay(500);
    }
    if(digitalRead(ri)==HIGH)
    {
      delay(500);
      i=i+1;
    }
    if(digitalRead(le)==HIGH)
    {
      delay(500);
      i=i-1;
    }
    if(digitalRead(ok)==HIGH)
    {
      lim=i;
      delay(500);
    }
  }
}

void loop()
{
  lcd.begin(16,2);
  lcd.setCursor(0,0);
  lcd.print("Type text:");
  intext();
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("Success!!");
  lcd.setCursor(0,1);
  lcd.print(input);
  delay(5000);
}