Hello Asok Sankar Rudra,
I made the same changes (see below) as you described in the same file and complied with SDCC.EXE. The file size remained the same. The binary image size was 885 bytes for both version.
Regards,
Charles Bannister
http://www.8052.com/forum/rea...&top=69242
File Modifications
hour = 18; to hour = 12" and
"if (hour >= 24)
{hour = 0;
to
if (hour >= 12)
{hour = 0;"

Hex Dump of file with above changes

:0400000002032D3298
:03000B00020031BF
:0100130032BA
:01001B0032B2
:0100230032AA
:01002B0032A2
:10032D00758126120329E582600302002C7900E90C
:10033D004400601B7A00900375780075A000E4936B
:10034D00F2A308B8000205A0D9F4DAF275A0FF787F
:10035D0000E84400600C7900900000E4F0A3D8FCA4
:08036D00D9FAF6D8FD02002CBC
:10002C0012007780FEC0E0C0F0C082C083C002C066
:10003C0003C004C005C006C007C000C001C0D07515
:10004C00D008438CDC052375D0001200D675D0087F
:10005C00D0D0D001D000D007D006D005D004D0032A
:10006C00D002D083D082D0F0D0E032D2AFD2A9432C
:10007C008901D28C7518FF75230075140C7513004B
:10008C007511007524FF751500751F12752001750B
:10009C002112752202752600751B40751C40751DBA
:1000AC0040751E40C3E523648094815005120110F5
:1000BC0080F275230012016112019C1202F71201E9
:1000CC00C21202B11202CB80DB220510C3E51094E0
:1000DC006440307510004315057517320511C3E5E2
:1000EC0011943C401E7511004315020513C3E51312
:1000FC00943C400F7513000514C3E514940C400395
:10010C0075140022751A087524FF7A007B00C3EA67
:10011C009404EB64809480503BE51AF4FCE5185C85
:10012C00F5B0EA241BF88604ECF4F590900005C0B9
:10013C0002C003120300D003D0027590FF74105557
:10014C00B0FCBC00028A24E51AC313F51A0ABA00E3
:10015C00BD0B80BA2275F00AE51384AAF0EA90036D
:10016C001F93FA8A1B75F00AE5138490031F93FA08
:10017C008A1C75F00AE51484AAF0EA90031F93FA1E
:10018C008A1D75F00AE5148490031F93FA8A1E22C7
:10019C0074045515FABA0002801B1517E517600E8A
:1001AC007480451CF51C7480451DF51D8007AA152F
:1001BC0074FB5AF51522E524B4FF0280487480556F
:1001CC0015FABA0040431580752532E52420E73531
:1001DC00C374838524F063F08095F04028E52425D2
:1001EC00E025249001F3730201FF020204020209CC
:1001FC0002020E120266800D12022B800812021DE2
:10020C008003120212220514E514B41803751400AD
:10021C00220513751100E513B43C03751300220578
:10022C0026E526B4011785141F851320751B007550
:10023C001C68751D78751E71120298800675260053
:10024C0012025022851421851322751B63751C63C1
:10025C00751D78751E7112029822E518F4FA747FD8
:10026C004AF51874805518FABA0011751B00751CE4
:10027C0000751D68751E78120298800F751B00752D
:10028C001C63751D63751E78120298227AD07B0749
:10029C00C002C003120110D003D0021ABAFF011B16
:1002AC00EA4B70EC2274805515FABA0002800F15D7
:1002BC0025E52560028007AA15747F5AF51522746E
:1002CC00015515FABA00028021AA1574FE5AF515CB
:1002DC00E514B51F08E513B5200375187FE514B5B3
:1002EC002108E513B522037518FF22E51EB43F0360
:1002FC00751E0022AA82AB837C007D00C3EC9AEDB4
:10030C0064808BF063F08095F050070CBC00ED0D11
:10031C0080EA223F0C765E4D5B7B0E7F5F75820020
:01032C0022AE
:00000001FF