Epic Systems Interview Question Software Engineer / Developers
Country: United States
Interview Type: Written Test
counter <= 3 or counter < 4
also counter + 1 will give a out of bound exception. this might work better:
char temp = ' ';
for(int counter=1; counter < 4; counter++)
{
temp = stringNumber[counter -1];
if(temp == stringNumber[counter+1])
status = false;
}
corrected code:
char temp = ' ';
for(int counter=1; counter < 4; counter++)
{
temp = stringNumber[counter -1];
if(temp == stringNumber[counter])
status = false;
}
public class Digits {
private int MAX;
private int[] digits;
private void print() {
for (int i = 0; i < digits.length; i++)
System.out.print(digits[i]);
System.out.println();
}
private void generate(int index) {
if (index == MAX)
print();
else {
if (digits[0] == 4 && index == MAX - 1) {
digits[index] = 4;
generate(index + 1);
} else {
for (int i = 0; i < 10; i++) {
if (index == 0 || digits[index - 1] != i) {
digits[index] = i;
generate(index + 1);
}
}
}
}
}
public void printDigits(int max) {
this.MAX = max;
this.digits = new int[MAX];
generate(0);
}
public static void main(String[] args) {
new Digits().printDigits(4);
}
}
// Recursive C# implementation that can handle a variable number of digits and
// skips ranges of numbers that don't meet the criteria
//
// Disadvantage of additional string creation
//
public static class UniqueDigits
{
public static void Display(int numDigits)
{
if (numDigits < 2)
{
throw new ArgumentOutOfRangeException(
"numDigits",
"Display requires numDigits to be greater than 1.");
}
for (int i = 1; i < 10; i++)
{
ExpandDigits(i.ToString(), i, 1, numDigits, i == 4);
}
}
private void ExpandDigits(string currentList,
int previousNumber,
int digitIndex,
int numDigits,
bool startsWithFour)
{
bool isLastDigit = digitIndex == numDigits - 1;
bool isSecondToLastDigit = digitIndex == numDigits - 2;
if (isLastDigit && startsWithFour)
{
Console.WriteLine(String.Concat(currentList, "4"));
}
else
{
for (int i = 0; i < 10; i++)
{
if ((i == previousNumber) || (isSecondToLastDigit && i == 4))
{
continue;
}
string number = String.Concat(currentList, i.ToString());
if (isLastDigit)
{
Console.WriteLine(number);
}
else
{
ExpandDigits(number, i, digitIndex + 1, numDigits, startsWithFour);
}
}
}
}
}
<pre lang="" line="1" title="CodeMonkey12882" class="run-this">public class cc1
{
public static void main (String args[])
{
int i=1,j=1,k=1;
for(i=1;i<10;i++)
{
for(j=1;j<10;j++)
{
if(j==i)
continue;
else
{
for(k=1;k<10;k++)
{
if(j==k)
continue;
else
{
if(i==4)
System.out.println(i+" "+j+" "+4);
else
{
System.out.println(i+" "+j+" "+k);
}
}
}
}
}
}
}
}</pre><pre title="CodeMonkey12882" input="yes">
</pre>
#include<stdio.h>
int check(int x) {
int i,num[4],t,flag=1;
for(i=3;i>=0;i--)
{
num[i]=x%10;
x=x/10;
}//end for
for(i=0;i<3;i++){
if (num[i]==num[i+1])
flag=-1;
}//end for
if(num[0]==4 && num[3]!=4)
flag=-1;
return flag;
}
int main()
{
//printf("hello world");
int i,num=1000,flag;
while(num<=9999)
{
flag=check(num);
if(flag==1) { printf("%d\n",num); }
num++;
}
return 0;
}
public class Digits {
private int MAX;
private int[] digits;
private void print() {
for (int i = 0; i < digits.length; i++)
System.out.print(digits[i]);
System.out.println();
}
private void generate(int index) {
if (index == MAX)
print();
else {
if (digits[0] == 4 && index == MAX - 1) {
digits[index] = 4;
generate(index + 1);
} else {
for (int i = 0; i < 10; i++) {
if (index == 0 || digits[index - 1] != i) {
digits[index] = i;
generate(index + 1);
}
}
}
}
}
public void printDigits(int max) {
this.MAX = max;
this.digits = new int[MAX];
generate(0);
}
public static void main(String[] args) {
new Digits().printDigits(4);
}
}
#include <stdio.h>
int main(void){
int i = 0;
int temp = 0;
int dig1, dig2, dig3, dig4;
for( i = 1010; i <= 9898; i++){
temp = i;
dig1 = temp / 1000;
temp = temp % 1000;
dig2 = temp / 100;
temp = temp % 100;
dig3 = temp / 10;
dig4 = temp % 10;
if ( (dig1 == 4 && dig4 == 4 && dig2 != dig3 && dig2 != 4) ||
(dig1 != 4 && dig1 != dig2 && dig2 != dig3 && dig3 != dig4) )
printf("%-10d", i);
else // not necessary to write else continue;
continue;
}
}
void num(string s){
if(s.length() < 4){
if (s.length() == 3 && s[0] == '4')
num(s + '4');
else{
for(char i = '0' ; i <= '9' ; ++i){
if(s[s.length() - 1] != i)
num(s+ i);
}
}
}
else{
cout << s << endl ;
}
}
int main(int argc, char **argv){
string s;
for(char i = '1' ; i <= '9' ; ++i)
num(s + i );
}
/*Generate all possible unique 4 digit numbers such that
no two adjacent numbers are the same and any number starting
with 4 should end with a 4 . eg 1234 , 1232 are both correct but 1223 is not .*/
public class FourDigit {
public static void main(String abc[]){
int count=0;
for(int i=1000;i<=9999;i++){
int number = i;
int firstdigit = number/1000;
int seconddigit = (number-(firstdigit*1000))/100;
int thirddigit = (number-(firstdigit*1000)-(seconddigit*100))/10;
int fourthdigit = (number-(firstdigit*1000)-(seconddigit*100)-(thirddigit*10))%10;
if((firstdigit==4)&&(fourthdigit==4)){
if((firstdigit!=seconddigit) && (seconddigit!=thirddigit) && (thirddigit!=fourthdigit))
System.out.println(i);
count++;
}
else{
if((firstdigit!=seconddigit) && (seconddigit!=thirddigit) && (thirddigit!=fourthdigit))
System.out.println(i);
count++;
}
}
System.out.println("count is "+count);
}
}
Works for not just 4 but for any other number of digits.
#include <iostream>
using namespace std;
void Generate (int& val, int curr, int dig, bool four) {
if (curr == dig) {
cout << val << "\t";
return;
}
if (four == true && (curr == dig - 1)) {
if (val % 10 != 4) cout << val * 10 + 4 << "\t";
return;
}
for (int i = 1; i <= 9; i++) {
if (val % 10 != i) {
val = val * 10 + i;
Generate (val, curr + 1, dig, four);
val = val / 10;
}
}
}
int main ( ) {
int dig, val;
cout << "Enter the number of digits: ";
cin >> dig;
for (int i = 1; i <= 9; i++) {
if (i == 4) Generate (i, 1, dig, true);
else Generate (i, 1, dig, false);
}
return 0;
}
/**
*
*/
/**
* @author apoorvagarwal
*
*/
public class PrintDigits {
/**
* @param args
*/
static void makeNumber(int a, int b, int c,int d){
System.out.println(""+a+b+c+d);
}
static void makeNumber(int focus,int length,String number){
if(length == 4 && number.charAt(0) == '0')
return;
if(length == 4 && number.charAt(0) == '0')
return;
if(length == 4 && number.charAt(0) == '4' && number.charAt(3) != '4'){
//System.out.println(""+number);
return;
}
if (length == 4 && (number.charAt(0)!='0')){
System.out.println(""+ number);
return;
}
else{
for(int i = 0;i<=9;i++){
//System.out.println(""+ number +" "+ focus);
if(number.length()>0 && (number.charAt(focus-1)-48 == i))
continue;
number = number + i;
makeNumber(focus+1, length+1, number);
number = number.substring(0, focus);
}
}
}
public static void main(String[] args) {
makeNumber(0,0,"");
}
}
void GenerateNum()
{
char d[4];
int factor = 1000;
int temp = 0;
for(int num = 1000; num < 9999; num++)
{
int temp = num;
for(int j = 3; j >= 0; j--)
{
d[j] = temp % 10;
temp /= 10;
}
if(d[0] == 4 && d[3] != 4) continue;
if(d[0] == d[1] || d[1] = d[2] || d[2] == d[3]) continue;
printf("%d", num);
}
}
#include <stdio.h>
#include <stdlib.h>
int main()
{
int i;
for(i=1000;i<10000;i++)
if(check(i))
printf("%d\n", i);
return 0;
}
int check(int a)
{
int d1, d2,d3, d4;
d1 = a/1000;
d2 = (a/100)%10;
d3 = (a/10)%10;
d4 = a%10;
if(d1 == 4 && d4 != 4)
return 0;
else if(d1 != d2 && d2 != d3 && d3 != d4)
return 1;
else
return 0;
}
public class FourDigitUniqueNumber
{
public static int i, j, k =0;
public static String temp;
public static void main(String[] args)
{
for(i=1230;i<10000;i++)
{
temp = String.valueOf(i);
j = (int)(temp.charAt(0))-48;
k = (int)(temp.charAt(3))-48;
if((temp.charAt(0)!= temp.charAt(1)) && (temp.charAt(1)!= temp.charAt(2)) && (temp.charAt(2)!= temp.charAt(3)))
{
if(j!=4)
System.out.println(temp);
else if(k==4)
System.out.println(temp);
}
}
}
}
#include <stdio.h>
void genNum(int dig, char *c, int pos, int len)
{
if (pos == len)
{
int p = 1;
c[pos] = '\0';
if (c[0] == '4')
{
if (c[len-1] != '4')
p = 0;
}
if (p)
printf("\n%s", c);
return;
}
else
{
int i;
for (i=0;i<=9;i++)
{
if (i != dig) {
//printf("i=%d", i);
c[pos] = i+'0';
genNum(i, c, pos+1, len);
}
}
}
}
int main()
{
char c[100];
genNum(0, c, 0, 3);
}
Here is a working code in C++. I have considered that a 4-digit number cannot start with 0. Though I have considered it, we can remove this restriction by deleting a few lines of code.
#include<cstdio>
#include<iostream>
using namespace std;
int func(int * arr,int *brr, int st,int ct, int prev);
int func(int * arr,int *brr, int st,int ct, int prev)
{
int i;
if (ct==2)
{
cout<<4;
for (i=0; i<2; i++)
{
cout<<brr[i];
}
cout<<4<<endl;
}
else
{
for (i=0; i<9; i++)
{
if (arr[i]==prev || (ct==0 && arr[i]==0))
{
continue;
}
brr[ct]=arr[i];
func(arr, brr, i+1, ct+1, arr[i]);
}
}
return 1;
}
int hello(int * arr1,int *brr1, int st1,int ct1, int prev1);
int hello(int * arr1,int *brr1, int st1,int ct1, int prev1)
{
int i;
if (ct1==4)
{
for (i=0; i<4; i++)
{
cout<<brr1[i];
}
cout<<endl;
}
else
{
for (i=0; i<9; i++)
{
if ((ct1==0 && arr1[i]==4) || (arr1[i]==0 && ct1==0))
{
continue;
}
if (arr1[i]==prev1)
{
continue;
}
brr1[ct1]=arr1[i];
hello(arr1, brr1, i+1, ct1+1, arr1[i]);
}
}
return 1;
}
int main()
{
int arr[]={1,2,3,5,6,7,8,9,0}, brr[2], brr1[4], arr1[]={0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
func(arr, brr, 0, 0, -1);
cout<<"next"<<endl;
hello(arr1, brr1, 0, 0, -1);
return 0;
}
print(0, 0, 4, 1, false, true);
private static void print(int number, int prev, int n, int start, boolean starts4, boolean firstTime) {
if(n==0){
System.out.println(number);
return;
}
for(int i=start; i<=9; i++){
if (firstTime && i == 4) {
print(number*10 + i, i, n-1, 0, true, false);
} else {
if ((n - 1) == 0 && starts4) {
if (prev != i && i == 4)
print(number*10 + i, i, n-1, 0, starts4, false);
} else if (prev != i)
print(number*10 + i, i, n-1, 0, starts4, false);
}
}
}
void PrintNumbersWithNoAdjacentSame(int subNum, int index, int numberLength)
{
if (numberLength == 0)
{
// skip number is it starts with 4 but doesn't end with 4
if ((subNum > 4000 && subNum < 5000) && subNum % 10 != 4)
return;
cout << subNum << ", ";
}
else
{
for (int i = 1; i < 10; ++i)
{
// Make sure no two adjacent numbers are same
if (subNum % 10 != i)
PrintNumbersWithNoAdjacentSame(subNum*10 + i, i + 1, numberLength - 1);
}
}
}
void PrintNumbersWithNoAdjacentSame()
{
int numberLength;
cin >> numberLength;
PrintNumbersWithNoAdjacentSame(0, 1, numberLength);
}
def valid(number):
isValid = True
if number[0] == '4' and number[3] != '4':
isValid = False
for i in range(len(number)-1):
if number[i] == number[i+1]:
isValid = False
return isValid
def gen():
for i in range(10000):
out = str(i)
if len(out) < 4:
out = '0'*(4-len(out)) + out
if valid(out):
print out
gen()
<pre lang="" line="1" title="CodeMonkey99618" class="run-this">/* C# implementation */
- rajeshkumar.a November 23, 2011public class UniqueFourDigits
{
public static void Display()
{
for (int currentNumber = 1000; currentNumber <= 9999; currentNumber++)
{
if (ContainsUniqueNumbers(currentNumber))
Console.WriteLine(currentNumber);
}
}
private static bool ContainsUniqueNumbers(int number)
{
bool status = true;
char[] stringNumber = number.ToString().ToCharArray();
for(int counter=0; counter < 3; counter++)
{
if(stringNumber[counter] == stringNumber[counter+1])
status = false;
}
if (status && stringNumber[0] == '4')
{
if (stringNumber[3] != '4')
{
status = false;
}
}
return status ;
}
}</pre><pre title="CodeMonkey99618" input="yes">
</pre>