CareerCup

Approach:
Construct each digit of the result one at a time, most to least significant. You'll find long division does exactly this - dividing numerator into denominator and multiplying the denominator by 10 every time. Simply repeat this for however many decimal places you want.

public void print(int num, int denom, int numDigits) {
    StringBuffer sb = new StringBuffer();

    // Compute number to left of decimal
    sb.append(num / denom);
    sb.append('.');
    num = (num % denom) * 10;

    // Compute each digit to the right of the decimal
    while (numDigits > 0) {
        sb.append(num / denom);
        num = (num % denom) * 10;
        numDigits--;
    }
    System.out.println(sb.toString());
}

#include <stdio.h>

void print_ndigit(int d, int n, int count) {
     int curr = d % n;
     for (int i=0;i<count;++i) {
         curr *=10;
         printf("%d ", curr/n);
         curr = curr % n;
     }
     printf("\n");
}

int main() {
    print_ndigit(3227,555,6);
    return 0;
}

class GetNDigitOfRationalNumber {
    public double solution(int numerator, int denominator, int num) throws ArithmeticException{
        double out = 0;
        double temp = (float) numerator/denominator;
        out = (int)(temp * Math.pow(10, num));
        return (float) (out/Math.pow(10, num));
    }
    
    private String getOutput(int numerator, int denominator, int num) throws ArithmeticException{
        String str = "";
        int pre = (numerator/denominator + "").length();
        double temp = (float) numerator/denominator;
        str = str+temp;
        System.out.println(str.substring(0,num+pre+1));
        return str;
    }
    
    public double solution2(int numerator, int denominator, int num) throws ArithmeticException{
        return Double.parseDouble(getOutput(numerator, denominator, num));
    }
}

class GetNDigitOfRationalNumber {
    public double solution(int numerator, int denominator, int num) throws ArithmeticException{
        double out = 0;
        double temp = (float) numerator/denominator;
        out = (int)(temp * Math.pow(10, num));
        return (float) (out/Math.pow(10, num));
    }
    
    private String getOutput(int numerator, int denominator, int num) throws ArithmeticException{
        String str = "";
        int pre = (numerator/denominator + "").length();
        double temp = (float) numerator/denominator;
        str = str+temp;
        System.out.println(str.substring(0,num+pre+1));
        return str;
    }
    
    public double solution2(int numerator, int denominator, int num) throws ArithmeticException{
        return Double.parseDouble(getOutput(numerator, denominator, num));
    }
}

public void formatRational(int numerator, int denominator, int N) {
String format = "%." + (N + 1) + "f";
String value = String.format(format, (numerator / (float)denominator));
int index = value.indexOf(".");
System.out.println(value.substring(0, index + 1) + value.substring(index + 1, index + 1 + N));
}

public void formatRational(int numerator, int denominator, int N) {
String format = "%." + (N + 1) + "f";
String value = String.format(format, (numerator / (float)denominator));
int index = value.indexOf(".");
System.out.println(value.substring(0, index + 1) + value.substring(index + 1, index + 1 + N));
}

void PrintNDigits(uint32_t num, uint32_t den, uint32_t max){
	if (den == 0){
		printf("Error");
	}
	else
	{
		// get integer of dividing 2 numbers
		printf("%d.", num / den);
		for (uint32_t i = 0; i < max && (num%den > 0); i++){
			uint32_t val = num%den;
			num = val * 10;
			printf("%d", num / den);
		}
	}
	printf("\n");

}

void PrintNDigits(uint32_t num, uint32_t den, uint32_t max){
	if (den == 0){
		printf("Error");
	}
	else
	{
		// get integer of dividing 2 numbers
		printf("%d.", num / den);
		for (uint32_t i = 0; i < max && (num%den > 0); i++){
			uint32_t val = num%den;
			num = val * 10;
			printf("%d", num / den);
		}
	}
	printf("\n");
}

string IntegerDivide(int num, int den, int n)
{
	if (num == MINI && den == -1) throw overflow_error("result overflowed");

	ll x = num, y = den; int sign = (x >> 31) == (y >> 31) ? 1 : -1;

	x = abs(x); y = abs(y);

	string integer = to_string(x / y * sign), decimal;

	unordered_map<int, int> st; x %= y;

	while (x != 0 && st.count(x) == 0 && decimal.size() < n)
	{
		st[x] = decimal.size(); x *= 10; decimal += to_string(x / y); x %= y;
	}

	if (x == 0)
	{
		decimal += string(n - decimal.size(), '0');
	}
	else if (st.count(x) != 0)
	{
		string tmp = decimal.substr(st[x]);

		while (decimal.size() < n) decimal += tmp;
	}

	while (decimal.size() > n) decimal.pop_back();

	return decimal.empty() ? integer : integer + "." + decimal;
}

public static void printRational(int a, int b, int n) {

		String output = "";
		int div, mod, currA, currB, i;
		i = div = mod = 0;


		currA = a;
		currB = b;


		output += (a/b)+".";

		for (;i < n; i++) {

			mod = currA % currB;
			mod *= 10;

			while (mod < currB) {

				mod *= 10;
				output += "0";
				i++;
			}

			output += mod/currB+"";
			currA = mod;
		}

		System.out.println(output);
	}

void delenje(int x, int y, int n)
{
   double pow=1.;

   for(int k=0; k < n; ++k)
      pow *=10.;
   
   double z = static_cast<double> (x)/y;
   
   int i = z;
   
   double w=z-i;
   
   int j = w*pow;
   
   cout << i << "." << j << endl;

}

#! /usr/bin/ruby
# Write a function which, given two integers (a numerator and a denominator),
# print the first N digits of a rational number. For example, for 5 / 3 with
# N=5, the result should be "1.66666". N=2: 1.66

numer = ARGV[0].to_i
denom = ARGV[1].to_i
digits = ARGV[2].to_i

def div(numer, denom, digits)
  s = (numer / denom).to_s + "."
  digits.times do |i|
    numer %= denom
    numer *= 10
    s << (numer / denom).to_s
  end
  s
end

puts "Rational #{numer}/#{denom} => #{div numer, denom, digits}"
# vim:ts=2:sw=2:et:tw=120

#include <string>
#include <sstream>

using namespace std;

string div(int num, int den, int N) {
    stringstream ss;
    if (den == 0) return ss.str();
    
    ss << num / den;
    if (N == 0) return ss.str();
    ss << ".";
    
    int r = num % den;
    for (; N > 0; --N) {
        r *= 10;
        if (r < den) {
            ss << "0";
        } else {
            ss << r / den;
            r = r % den;
        }
    }
    return ss.str();
}

int main()
{
    for (;;) {
        int num;
        std::cout << "Numerator: "; cin >> num;
        int den;
        std::cout << "Denominator: "; cin >> den;
        int N;
        std::cout << "N: "; cin >> N;
        
        std::cout << "Result: " << div(num, den, N) << "\n";
    }
}

func foo(x, y, n int) {
	fmt.Print(x/y)
	x %= y
	fmt.Print(".")
	for i:=0; i<n; i++ {
		x *= 10
		fmt.Print(x/y)
		x %= y
	}
}

private static String GetNDigitsOfRationalNum(int numer, int denom, int digits)
        {
            string valStr = (numer / (double)denom).ToString();
            string integerPart, decimalPart;

            int deci = valStr.IndexOf(".");
            integerPart = valStr.Substring(0, deci);
            decimalPart = valStr.Substring(deci + 1, digits + 1);

            return integerPart + "." + decimalPart;
        }

Looks like that everyone forgot the possibility of getting negative number.

like -5/3, most of the solutions will give 1.-6-6

void nDigits(int n, int d, int c){
	cout << n / d << ".";

	int count = 0;

	while (count < c){
		n = (n%d) * 10;;

		cout << abs(n / d);
		count++;
	}
}

public static String division(int numerator,int denominator,int no_of_digits)
        {
            StringBuffer sb=new StringBuffer();
            sb.append((numerator/denominator)+".");
            while(no_of_digits-->0)
            {
                numerator=(numerator%denominator)*10;
                sb.append(numerator/denominator);
            }
            return sb.toString();

}

JavaScript:

var numerator = 5;
var denominator = 3;
var N = 6;

alert ( Math.floor ( numerator / denominator * Math.pow (10, N - 1) ) / Math.pow (10, N - 1) );

output: 1.66666

public static void printSizedDivision(int numerator, int divisor, int digits){
    StringBuilder line = new Stringbuilder();
    line.append(numerator / divisor);
    line.append('.');
    numerator %= divisor;
    while(numerator > 0 && digits > 0){
        numerator *= 10;
        line.append(numerator / divisor);
        numerator %= divisor;
        digits--;
    }
    System.out.println(line.toString());
}

#include<stdio.h>
#include<conio.h>
int main()
{
int a,b,count=0,n,rem,cons1;
float count2=0.1,cons;
printf("enter the value of a and b:=>");
scanf("%d%d",&a,&b);
printf(" enter the value of N:=> ");
scanf("%d",&n);
while(n>0)
{
if(count==0)
{
cons=a/b;
rem=a%b;
count++;
}
cons1=(rem*10)/b;
cons=cons+cons1*count2;
rem=(rem*10)%b;
count2=count2*0.1;
n--;
}
printf("%f",cons);
return 0;
}

This is a trivial question:
{{
public class DivisionPrint {

public static void print(int num, int denom, int n) {
if (denom == 0) {
throw new RuntimeException("denom cannot be zero ...");
}

double result = (double) num / denom;
int res = (int) result;
String output = res + ".";

double precision = result - (double) res;

int fp = (int)(precision * Math.pow(10, n));

output += fp + "";

System.out.println(output);
}

public static void main(String[] args) {
DivisionPrint.print(5, 3, 5);
DivisionPrint.print(5, 3, 2);
}
}
}}

public void printNDigitsOfRationalNumber(int numerator, int denominator, int digits) {
        String stringRep = (numerator / (double) denominator) + "";
        int dotIndex = stringRep.indexOf(".");
        String output = stringRep.substring(0, dotIndex);

        for (int i = dotIndex, j = 0; i < stringRep.length() && j <= digits; i++, j++) {
            output += stringRep.charAt(i);
        }

        System.out.println("Output: " + output);

}

package fraction generator;
import java.util.Scanner;
public class JavaApplication19 {
       public static void main(String[] args) {
        int nume,denume,n,temp_res,res1,i,rem;
        float temp2,temp3,res;
        System.out.println("enter numerator ,denominator ,and limit");
        Scanner in=new Scanner(System.in);
        nume=in.nextInt();
        denume=in.nextInt();
        n=in.nextInt();
        res1=nume/denume;
        res=res1;
        rem=(nume%denume)*10;
        for(i=1;i<=n;i++)
        {
         temp_res=rem/denume;
         temp2=(float) Math.pow(0.1,i);
         temp3=temp_res*temp2;
         res=res+temp3;
         rem=(rem%denume)*10;
        }
        System.out.println(res);
       } 
}

package fraction generator;
import java.util.Scanner;
public class JavaApplication19 {
       public static void main(String[] args) {
        int nume,denume,n,temp_res,res1,i,rem;
        float temp2,temp3,res;
        System.out.println("enter numerator ,denominator ,and limit");
        Scanner in=new Scanner(System.in);
        nume=in.nextInt();
        denume=in.nextInt();
        n=in.nextInt();
        res1=nume/denume;
        res=res1;
        rem=(nume%denume)*10;
        for(i=1;i<=n;i++)
        {
         temp_res=rem/denume;
         temp2=(float) Math.pow(0.1,i);
         temp3=temp_res*temp2;
         res=res+temp3;
         rem=(rem%denume)*10;
        }
        System.out.println(res);
       } 
}

Takes care of the sign, and just print the needed digits.

public string Division(int numerator, int denominator, int presicion)
{
	if (denominator == 0)
		throw new DivideByZeroException();
	
	StringBuilder sb = new StringBuilder();

	// The division takes care of the sign -
	sb.Append(numerator / denominator);

	numerator = Math.Abs(numerator);
	denominator = Math.Abs(denominator);

	numerator = (numerator %  denominator) * 10;
	if (numerator == 0)
		return sb.ToString();

	sb.Append('.');

	while(presicion > 0 && numerator != 0)
	{
		sb.Append(numerator / denominator);
		numerator = (numerator % denominator) * 10;
		presicion--;
	}

	return sb.ToString();
}

Considere the sign and just print the needed digits.

public string Division(int numerator, int denominator, int presicion)
{
	if (denominator == 0)
		throw new DivideByZeroException();
	
	StringBuilder sb = new StringBuilder();

	// The division takes care of the sign -
	sb.Append(numerator / denominator);

	numerator = Math.Abs(numerator);
	denominator = Math.Abs(denominator);

	numerator = (numerator %  denominator) * 10;
	if (numerator == 0)
		return sb.ToString();

	sb.Append('.');

	while(presicion > 0 && numerator != 0)
	{
		sb.Append(numerator / denominator);
		numerator = (numerator % denominator) * 10;
		presicion--;
	}

	return sb.ToString();
}

public void printRational( int num, int denom, int prec ) {
                String format       = "%." + prec + "f";
                String formattedVal = String.format( format, (double) num / denom );
                System.out.println( formattedVal );
        } // end printRational

int abs(int n)
{
   return (n < 0) ? -n : n;
}
void printFirstN(int N, int num, int denom)
{
   cout<<num/denom<<".";
   int  count = 0;
   int remainder = (num%denom)*10; 
   while(count < N)
   {   
       cout<<abs(remainder/denom);
       remainder = (remainder%denom)*10;
       count++;
   }
   cout<<endl;

}
int main()
{
	printFirstN(5,-5,3);
        printFirstN(5,5,3);
        printFirstN(2,-5,3);   
        return 0;
}