Number of valid indices in the permutation of first N natural numbers | Python3 implementation of the approach ; Function to return the number of i 's such that Pi <= Pj for all 1 <= j <= i in the permutation of first N natural numbers ; To store the count of such indices ; Store the mini value ; For all the elements ; Return the required answer ; Driver code
import sys NEW_LINE INT_MAX = sys . maxsize NEW_LINE def min_index ( p , n ) : NEW_LINE INDENT ans = 0 ; NEW_LINE mini = INT_MAX ; NEW_LINE for i in range ( n ) : NEW_LINE INDENT if ( p [ i ] <= mini ) : NEW_LINE INDENT mini = p [ i ] ; NEW_LINE DEDENT if ( mini == p [ i ] ) : NEW_LINE INDENT ans += 1 ; NEW_LINE DEDENT DEDENT return ans ; NEW_LINE DEDENT if __name__ == " _ _ main _ _ " : NEW_LINE INDENT P = [ 4 , 2 , 5 , 1 , 3 ] ; NEW_LINE n = len ( P ) ; NEW_LINE print ( min_index ( P , n ) ) ; NEW_LINE DEDENT