Tag: number

grep for special characters in Unix

Tell grep to treat your input as a fixed string using -F option.

grep -F '*^%Q&$*&^@$&*!^@$*&^&^*&^&' application.log

Option -n is required to get the line number,

grep -Fn '*^%Q&$*&^@$&*!^@$*&^&^*&^&' application.log

Less: Quickly Jump to Line Number in Large File

If the file is open you can type:

  • 100g to go to the 100th line.
  • 50p to go to 50% into the file.
  • 100P to go to the line containing 100th byte.

You can use these from terminal by adding + in front of them:

less +100g bigfile.txt

bash: perform mathematical operations on strings

If VAR1 and VAR2 are strings having integer values like:
VAR1=”12″

VAR2=”2″

Then mathematical operations can be performed on it as below:
VAR3=$(echo “$VAR1 $VAR2” | awk ‘{print $1+$2}’)

OR you can also use:
VAR3=$(awk ‘{print $1+$2}’ <<<“$VAR1 $VAR2”)

Java 8 coding challenge : Jarvis and Seven Segments

All over the world, peoples are working on energy solution. It would be a tough time for our next generation to survive if we don’t think about solution. Tony stark is working on a new project and wants to display his project using “seven segment display – concept”. Tony Stark gave Jarvis a task to find a number from his Favorite list of number for which the energy consumption is lowest.

(Assuming that for a digit to represent Tony stark is using 7 bulbs and only those bulbs light up which are required to represent a number and rest other would be completely off.)

Help Jarvis and conserve energy.

Seven segment display – https://en.wikipedia.org/wiki/Seven-segment_display

enter image description here

Input:
First line will contain the number of test cases and for every test case first line will contain length of favorite list and the second line for a test case will contain n numbers

Output:
For every test case print the answer. If there exist more than 1 numbers for which same number of bulbs are required than output the number which occurs first in the Favorite list.

Constraints:
Test cases< 10
A[i] < 10^6
Size of list < 10^5

SAMPLE INPUT
1
5
1 2 3 4 5
SAMPLE OUTPUT
1
Explanation

Number 1 needs only two bulbs to represent.

Code:

import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.HashMap;
 
 
 
 
public class Solution {
 
 
 public static void main(String args[]) throws IOException{
 InputReader in=new InputReader(System.in);
 PrintWriter out=new PrintWriter(System.out);
 int T=in.readInt();
 
 while(T-->0){
 long N=in.readLong();
 long min=222222222;
 long minnum=0;
 while(N-->0){
 long num=in.readCount();
 long count=in.getcount();
 if(count<min){
 min=count;
 minnum=num;
 }
 }
 out.println(minnum);
 out.flush();
 
 }
 
 out.close();
 
 }
}
 
class InputReader{
 InputStream in;
 int[] segment={6,2,5,5,4,5,6,3,7,6};
 long count=0;
 InputReader(InputStream in){
 this.in=in;
 }
 
 public long getcount(){
 return count;
 }
 private int read() throws IOException{
 return in.read();
 }
 
 
 
 public char readChar() throws IOException{
 int n=read();
 while(isWhiteSpace(n)){
 n=read();
 }
 return (char)n;
 }
 
 public int readInt() throws IOException{
 int number=0;
 int n=read();
 while(isWhiteSpace(n)){
 n=read();
 }
 while(!isWhiteSpace(n)){
 int integer=n-'0';
 number*=10;
 number+=integer;
 n=read();
 }
 return number;
 }
 
 public long readCount() throws IOException{
 long number=0;
 count=0;
 int n=read();
 while(isWhiteSpace(n)){
 n=read();
 }
 while(!isWhiteSpace(n)){
 int integer=n-'0';
 count+=segment[integer];
 number*=10;
 number+=integer;
 n=read();
 }
 return number;
 }
 
 
 public long readLong() throws IOException{
 long number=0;
 int n=read();
 while(isWhiteSpace(n)){
 n=read();
 }
 while(!isWhiteSpace(n)){
 int integer=n-'0';
 number*=10;
 number+=integer;
 n=read();
 }
 return number;
 }
 
 private boolean isWhiteSpace(int n){
 if(n=='\n'||n=='\r'||n=='\t'||n==' '||n==-1){
 return true;
 }else{
 return false;
 }
 
 }
 }