continued HOW MANY PERMUTATION EXIST?

1 2 3 4
1 ♛
2 ♛
3 ♛
4 ♛

test : Q1 : N Q2 : N-1 Q3 : N-3 Q4 : 1

not considering diagonal eliments in table above and is just general soln how our solution can be obtained

Worst case Time complexity : O(N!)

1 2 3 4
1 ♛
2 ♛
3 ♛
4 ♛

Best case time complexity : O(n) at every row very first trial of column is sucessful It is linear time in number of rows

graphcoloring

graph coloring refers to the problem of coloring vertices of a graph in such a way that no two adjacent vertices have same color

minimum number of colors needed to color a graph is called its chromatic number

1000186740.heic

set={R,G,B}

Possible Solutions : 3^4 ( no of colors ^ no of vertices )

BACKTRACKING : STATE SPACE TREE

graph TD
  A --RED--> B
  B--RED--> NoSoln1 
  B--GREEN--> C
  C--RED-->D

  D--RED--> NoSoln2
  D --GREEN--> Soln1
  D--BLUE-->Soln2