iterate over all pair of strings
pairs = 0 NEW_LINE for i in range ( 0 , len ( v ) ) : NEW_LINE INDENT for j in range ( i + 1 , len ( v ) ) : NEW_LINE INDENT if ( isPanDigital ( v [ i ] + v [ j ] ) ) : NEW_LINE INDENT pairs = pairs + 1 NEW_LINE DEDENT DEDENT DEDENT return pairs NEW_LINE