第二章：开始学习C++//ex2.1--disｐｌay ｙｏuｒ nａmｅ ａnｄ adｄress#inｃluｄｅinｔ mａin(void）{ﻩｕｓinｇ ｎamｅｓpａce std;ﻩcout<＜"Ｍｙ name iｓ ｌｉaｏ ｃhｕngｕａng anｄ I liｖe in hｕｎａn cｈenｚhｏｕ.\n”；}/／ex2.2－－cｏｎvert tｈｅ ｆuｒｌong units ｔｏ yard ｕints-把浪单位换位码单位#inclｕｄe＜ｉｏｓtreaｍ>douｂle fｕr2ｙd(dｏublｅ);int maｉn(){ﻩusｉng ｎａｍｅspａcｅ std；ﻩｃｏuｔ<<"enter the ｄisｔaｎce ｍｅaｓuｒed bｙ fｕｒlonｇ unｉtｓ：";ﻩdｏubｌe ｆuｒ；ﻩciｎ>＞ｆur;ﻩcｏut<<＂ｃonｖｅrｔ ｔｈe ｆuｒlｏng ｔｏ yard＂<＜eｎdl;doublｅ ｙd;ﻩｙd＝fur2yd(ｆｕｒ）;ﻩcoｕｔ＜vｏid mice()；vｏid sｅe（);using ｎamesｐace sｔｄ;int main()｛ﻩｍｉｃe（);ﻩｍice()；ﻩsee()；ﻩsee(); reｔurn 0;｝vｏid ｍice(){ﻩcｏut<＜"three blｉnd mice"<＜endｌ；}vｏｉｄ ｓｅe(）{ﻩcout<<"seｅ hｏw tｈey ruｎ"＜＞agｅ； int montｈ； month=age*１2; coｕt<＜ａgｅ<<" ｙeaｒs ｉs "<＜mｏntｈ<<" mｏntｈs"<dｏuｂle C２Ｆ(ｄoubｌe）;int maｉn(）｛ｕsing ｎａｍｅsｐaｃe std；coｕt<<＂ｐleaｓe ｅｎter a Cｅlsiｕs ｖalｕｅ:＂;doubｌe C；cin>＞C；ｄoublｅ F；F=Ｃ2F(C)；cｏut<＜C<<" dｅｇreｅｓ Cｅlsius ｉｓ ＂<＜F<＜" degreeｓ Fahrenheｉt．＂＜<ｅndl;retｕrn ０;｝ｄouble Ｃ2F(doｕble t）{rｅｔｕrn １．8*t+3２；} ／/eｘ2．6－--converｔ tｈｅ lｉght yｅａrs ｖalve to astroｎoｍｉcａｌ ｕnits--把光年转换为天文单位＃ｉｎcludｅ<ｉosｔreａｍ>dｏuble ｃonｖｅrｔ(douｂｌｅ)；//函数原型int main(){uｓinｇ ｎａmｅｓpａce std;ｃouｔ<<＂Ｅnｔeｒ the number of ligｈt ｙeａｒs:"；double liｇｈt_years;ｃin>＞ｌｉght_ｙeａrs；ｄouble aｓｔｒo＿unｉts；astｒo_uｎiｔs=ｃonvｅｒt(light＿yｅａrｓ);ｃoｕt<>ｈ;cｏut<<＂ｅntｅｒ tｈｅ nｕmbｅｒ ｏｆ minｕｔes:＂；cin＞>m；ｃout<<＂Ｔｉｍｅ:"＜ｃonsｔ int ｉnｃh_per_feｅｔ=12;／/ ｃｏｎｓt常量--1fｅet=12ｉncｈeｓ--1英尺=12英寸ｉnt maｉn(){ uｓｉnｇ nａmeｓｐａcｅ std;ﻩcoｕt＜<"pleａse ｅnｔeｒ youｒ ｈeigｈt ｉｎ inches:___\b＼b\ｂ";/／ \b表达为退格字符 int ｈt_inｃh;ﻩcｉn>>ht_ｉnｃh；ﻩｉnt ht_feet＝ht＿ｉnｃh/inch＿ｐeｒ_feeｔ;／/取商ﻩint ｒｍ_iｎch＝ht＿iｎｃｈ％ｉnｃh＿per_feeｔ;//取余 ｃout＜<"your hｅighｔ iｓ "＜＜ht_fｅｅt<＜" ｆeet,ａｎd ＂ﻩﻩ＜＜ｒm＿incｈ<<" iｎｃhｅs＼n";ﻩｒｅturｎ 0；｝／／ex３.２－－计算相应的body maｓs index（体重指数)#ｉnclｕdecｏnsｔ iｎt ｉnch_per_feeｔ＝１２；ｃonst doｕblｅ mｅｔer_per＿inch=０.02５4；cｏnsｔ ｄoubｌe pｏund＿per_ｋilogｒａm=２.2；ｉｎt maｉｎ（）{ﻩusiｎg naｍespace sｔｄ；ﻩcout<<＂Pleaｓｅ ｅｎｔeｒ your hｅigｈt:"<>ht＿fｅｅt; ｃoｕｔ<＜＂Second,entｅr your heｉghｔ oｆ ｉｎcｈ parｔ(输入你身高的英寸部分）:_\b";ﻩｉｎt hｔ＿inｃｈ;ﻩｃin>>hｔ_inch；ﻩcｏut＜＜"Now,pｌｅasｅ entｅｒ your weighｔ ｉn pound：__＿＼b\b＼b";ﻩｄoｕｂlｅ wｔ＿poｕnｄ;ﻩcin>>wt_pｏunｄ；ﻩint ｉｎch; incｈ=hｔ_feeｔ＊iｎch_ｐeｒ_fｅｅt＋ｈｔ_inch；ﻩdoｕble ht_meter;ﻩht_mｅtｅｒ＝inｃh*mｅteｒ＿pｅｒ_iｎch;ﻩｄｏuｂle wt_kilｏgram;ﻩwt_ｋｉｌogram=wt_pound／pｏuｎｄ＿per_ｋｉlogｒａm;ﻩcｏuｔ<ｃonｓｔ ｉｎｔ mｉnutｅs_ｐｅｒ_degree＝6０;consｔ int secoｎｄｓ_peｒ_mｉｎute=60;int maiｎ(）{ﻩｕsing namesｐacｅ stｄ；ﻩcout＜<＂Ｅｎｔｅr a lａtiｔudｅ iｎ degrees,minuteｓ，ａnｄ secｏｎｄｓ:＼ｎ"; couｔ＜＜"Fｉrst，eｎteｒ ｔｈe degｒｅes："；ﻩiｎt ｄｅgｒee;ﻩciｎ>>degrｅｅ;ﻩcouｔ＜<"Neｘｔ,enｔer ｔｈe ｍinuｔeｓ oｆ arc:"; iｎt ｍinutｅ；ﻩciｎ＞>ｍiｎute;ﻩcｏuｔ＜＜"Fｉanlｌy，ｅnter tｈe sｅcondｓ ｏf ａｒc:"; iｎｔ secｏnd；ﻩｃiｎ＞＞sｅcond；ﻩdoｕble show_in_degree；ﻩsｈow＿in_dｅｇreｅ=(doublｅ)degrｅe+(doｕble)ｍinutｅ/minuｔｅs＿ｐer＿degree＋(doｕbｌe)second/ｍiｎuｔeｓ_per_deｇｒｅe/sｅｃonｄｓ_per＿minuｔe；ﻩｃｏｕt＜ｓeｃonds;ﻩｉnt Ｄay,Hoｕｒ，Ｍinute,Seｃonｄ; Ｄay=secｏｎｄs／seconｄs＿ｐer_minｕte/minutｅs_ｐｅr_hｏur/hｏurs_per＿daｙ;ﻩＨｏuｒ=seｃonds/seconｄｓ_ｐeｒ_minｕte/minutes_per_hｏur％ｈourｓ＿ｐeｒ_ｄay;ﻩＭiｎuｔe=seｃonds/secoｎds_ｐｅr＿minuｔe％mｉnutes_pｅr_ｈouｒ; Ｓｅconｄ＝secoｎds%seｃｏnds＿peｒ_miｎuｔe；ﻩｃoｕt<<ｓeｃoｎｄｓ＜＜＂sｅconｄｓ = "＜＜Ｄay<＜" ｄａyｓ，＂<<Ｈouｒ＜＜＂ hours,＂<
