/*Format : LIMIT a - 1, b - (a - 1)
ROUND(lat/lon, n)
ORDER BY city DESC(ra) OR ASC(al)
*/
SELECT ROUND(MAX(SQRT(POW(x1 - x2, 2) + POW(y1 - y2, 2))), 4),

# 14) Swap(lat, lon) by ID parity check
UPDATE citytable
SET lat = lat + lon, lon = lat-lon, lat = lat - lon
WHERE CASE WHEN 'od' = 'ev' THEN id % 2 = 0
ELSE id % 2 = 1 END;

#include <iostream>
#include <vector>
#include <stack>
#include <algorithm>
using namespace std;

#Format : LIMIT s-1, t - (s - 1)
SELECT ROUND(ABS(x1 - x2) + ABS(y1 - y2), 4)
FROM (SELECT MIN(lon) x1, MAX(lon) x2
FROM (SELECT*FROM citytable
WHERE lat < 121.8 ORDER BY lat DESC LIMIT 3, 15) AS Table1) AS latTable,

swaggerwall# arp -a | grep '9c:22'
10.16.89.1 9c:22:92:38:34:10 vlan10 permanent l
10.16.89.65 9c:22:92:38:34:20 vlan20 permanent l

#Format : LIMIT s-1, t - (s - 1)

SELECT COALESCE(ROUND(AVG(val), 4), 'NULL')
FROM (SELECT CASE WHEN 'lon' = 'lat' THEN lat ELSE lon END AS val, @rownum:=@rownum+1 AS idx, @total_rows:=@rownum
FROM citytable x, (SELECT @rownum:=0) r

#include <iostream>
#include <sstream>
#include <algorithm>
using namespace std;

[root@swaggserver-01 httpd]# cat access_log-20191* | awk '$7 ~/\.php/ {print $4}' | sort | uniq -c | sort -r | head
13 [27/Nov/2019:16:18:08
12 [26/Nov/2019:17:36:17
12 [24/Nov/2019:05:20:51
11 [23/Nov/2019:00:48:57

[root@swaggserver-01 log]# tail -n 20 swaggnet.log
Dec 19 01:15:15 fdc5:acbd:5ab1:d9cf::1 158: Dec 19 06:15:14.897: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: daniel] [Source: 10.15.89.246] [localport: 22] at 01:15:14 EST Thu Dec 19 2019
Dec 19 01:20:08 gateway 1852: Dec 19 06:20:05.898: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: daniel] [Source: 10.15.89.246] [localport: 22] at 01:20:05 EST Thu Dec 19 2019
Dec 19 01:20:08 fdc5:acbd:5ab1:d9c6::1 1852: Dec 19 06:20:05.898: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: daniel] [Source: 10.15.89.246] [localport: 22] at 01:20:05 EST Thu Dec 19 2019
Dec 19 01:20:13 gateway 1853: Dec 19 06:20:11.108: %SEC_LOGIN-5-LOGIN_SUCCESS: Login Success [user: daniel] [Source: 10.15.89.246] [localport: 22] at 01:20:11 EST Thu Dec 19 2019

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;