1 00:00:00,000 --> 00:00:00,580 2 00:00:00,580 --> 00:00:02,950 >> DAVID J. Malan: Hebu sasa kutekeleza kazi ambayo si tu na upande 3 00:00:02,950 --> 00:00:05,920 athari, lakini badala yake anarudi thamani ya kurudi. 4 00:00:05,920 --> 00:00:09,150 Hasa, hebu kutekeleza kazi aitwaye kupata int chanya ambao 5 00:00:09,150 --> 00:00:11,490 kusudi katika maisha ni kufanya hasa kwamba. 6 00:00:11,490 --> 00:00:14,500 Hasa, Ningependa kutumia kazi hii kama ifuatavyo - 7 00:00:14,500 --> 00:00:18,770 int N anapata kupata chanya int. 8 00:00:18,770 --> 00:00:23,640 Na kisha magazeti f, shukrani kwa asilimia i kama 9 00:00:23,640 --> 00:00:26,490 placeholder, comma, mwisho. 10 00:00:26,490 --> 00:00:29,030 >> Sasa bila shaka, kupata chanya int bado haina kuwepo. 11 00:00:29,030 --> 00:00:33,020 Basi hebu ahadi ya kutekeleza na kuongeza juu ya faili yangu line 12 00:00:33,020 --> 00:00:37,110 kama int ikimaanisha kwamba kazi hii atarudi katika int - 13 00:00:37,110 --> 00:00:39,110 kupata chanya int. 14 00:00:39,110 --> 00:00:43,000 Na hebu bayana waziwazi kwamba hii kazi si kuchukua mchango wowote, na 15 00:00:43,000 --> 00:00:45,570 hivyo hoja yake ni batili. 16 00:00:45,570 --> 00:00:49,500 Hebu sasa chini ya faili yangu, tu ili niweze kuweka kuu juu juu, 17 00:00:49,500 --> 00:00:52,220 kweli kutekeleza au kufafanua kazi hii. 18 00:00:52,220 --> 00:00:55,120 >> Kwanza sisi kuanza kwa moja sahihi, hivyo kusema - 19 00:00:55,120 --> 00:00:59,140 int kupata chanya int ni batili. 20 00:00:59,140 --> 00:01:01,910 Na sasa hebu kutekeleza kupata chanya int kama ifuatavyo. 21 00:01:01,910 --> 00:01:05,410 Hebu kutangaza int, pia hujulikana N lakini tunaweza kuiita karibu kila kitu 22 00:01:05,410 --> 00:01:11,360 tunatarajia, wala zifuatazo wakati baadhi hali ni ya kweli, na sisi itabidi kurudi kwa 23 00:01:11,360 --> 00:01:13,030 kwamba hali katika wakati huu. 24 00:01:13,030 --> 00:01:20,800 Magazeti f, tafadhali nipe chanya int, na sasa hebu kutumia Get int kutoka 25 00:01:20,800 --> 00:01:23,290 Maktaba CS50 kwa kweli kupata kwamba int. 26 00:01:23,290 --> 00:01:28,210 >> Lakini katika hali yangu, hebu kufanya hivyo kitanzi kwa muda mrefu kama N ni chini ya 1. 27 00:01:28,210 --> 00:01:31,260 Kwa maneno mengine, hivyo muda mrefu kama user haina kushirikiana na kutoa yangu 28 00:01:31,260 --> 00:01:36,260 na chanya int, napenda tena haraka kwake tena na tena, na tena 29 00:01:36,260 --> 00:01:37,720 mpaka yeye au yeye hana. 30 00:01:37,720 --> 00:01:40,360 Lakini mimi si kufanyika bado, kwa sababu mwisho wa kazi hii mimi haja ya 31 00:01:40,360 --> 00:01:42,210 kweli kufanya kitu na pembejeo hiyo. 32 00:01:42,210 --> 00:01:46,710 Na hivyo mimi nina kwenda kuhusu kurudi ni pamoja na line kama kurudi mwisho 33 00:01:46,710 --> 00:01:52,850 semicolon, na hivyo kurudi halisi int kuu ambao aliwaita kazi hii. 34 00:01:52,850 --> 00:01:56,810 Sasa ni thamani kubainisha kwamba hata kama kupata chanya int kurudi katika int, ni 35 00:01:56,810 --> 00:02:00,470 hakika faini kwa kuwa na kurudi int chanya hasa. 36 00:02:00,470 --> 00:02:04,170 Kuna si aina maalum data kwa integer chanya hasa, hivyo sisi 37 00:02:04,170 --> 00:02:06,490 tu kutumia kujengwa katika "int." 38 00:02:06,490 --> 00:02:11,250 >> Sasa nyuma katika mstari wa tisa, taarifa kwamba mimi nina uchapishaji nje N. Lakini N katika mstari huu 39 00:02:11,250 --> 00:02:13,970 ni mali ya N hiyo alitangaza katika line nane. 40 00:02:13,970 --> 00:02:17,840 Hivyo ni zamu nje unaweza kabisa na vigezo identically aitwaye hivyo 41 00:02:17,840 --> 00:02:20,250 muda mrefu kama zipo ndani ya scopes tofauti. 42 00:02:20,250 --> 00:02:24,950 Na kukumbuka kwamba wigo ni inavyoelezwa na braces curly kwamba karibu sana 43 00:02:24,950 --> 00:02:27,620 yanayozunguka variable kwamba umefanya huo. 44 00:02:27,620 --> 00:02:30,370 >> Sasa hebu kukusanya na kuendesha mpango huu. 45 00:02:30,370 --> 00:02:35,210 Kufanya kazi 1, dot kufyeka kazi 1. 46 00:02:35,210 --> 00:02:40,040 Hebu kutoa chanya int-kama 50, na inasema shukrani kwa ajili ya 50. 47 00:02:40,040 --> 00:02:43,180 Wakati huo huo, kama hatuwezi kushirikiana, kuendesha programu tena, kutoa ni 48 00:02:43,180 --> 00:02:47,550 0, mimi nina ilisababisha tena, au kutoa ni hasi 1, mimi nina ilisababisha tena. 49 00:02:47,550 --> 00:02:51,720 Lakini kama mimi kushirikiana kutoa kwa, kusema, 50, mimi nina shukrani kwa 50. 50 00:02:51,720 --> 00:02:54,590