If left neighbor is valid and has value less than or equal to current cell 's value
if ( m - 1 >= 0 and adj [ n ] [ m ] >= adj [ n ] [ m - 1 ] and not visit [ n ] [ m - 1 ] ) : NEW_LINE INDENT dfs ( n , m - 1 , visit , adj , N , M ) NEW_LINE DEDENT def printMinSources ( adj , N , M ) : NEW_LINE