1 00:00:00,000 --> 00:00:00,330 2 00:00:00,330 --> 00:00:03,230 >> SPIKA: Hebu kutekeleza mpango huo humshauri mtumiaji kwa integer 3 00:00:03,230 --> 00:00:05,850 lakini inaendelea kusababisha yao kwa integer mwingine mpaka 4 00:00:05,850 --> 00:00:07,590 kwamba integer ni mazuri. 5 00:00:07,590 --> 00:00:16,760 Naam, hebu kuandika hii, ni pamoja na cs50.h, pamoja na kiwango io dot h, int 6 00:00:16,760 --> 00:00:18,010 kuu [utupu]. 7 00:00:18,010 --> 00:00:20,000 8 00:00:20,000 --> 00:00:23,200 Sasa hebu kweli kuanza haraka user kwa integer hii wakati kutunza katika 9 00:00:23,200 --> 00:00:25,570 akili kwamba tunataka reprompt yao mpaka 10 00:00:25,570 --> 00:00:26,860 idadi ni kweli chanya. 11 00:00:26,860 --> 00:00:30,160 >> Basi, mimi utasikia wanataka baadhi ya aina ya looping kujenga, lakini kitanzi kwamba executes katika 12 00:00:30,160 --> 00:00:31,200 angalau mara moja. 13 00:00:31,200 --> 00:00:34,810 Na kukumbuka do-kitanzi wakati inaruhusu sisi kufanya hasa kwamba. 14 00:00:34,810 --> 00:00:36,140 Hebu Kanuni hii up. 15 00:00:36,140 --> 00:00:39,210 >> Hebu kwanza kutangaza int - tutaweza kuiita n - ambayo kuhifadhi 16 00:00:39,210 --> 00:00:41,030 mtumiaji integer. 17 00:00:41,030 --> 00:00:44,250 Hebu sasa kufanya yafuatayo. 18 00:00:44,250 --> 00:00:51,292 Printf, tafadhali nipe chanya int. 19 00:00:51,292 --> 00:00:54,470 Hebu sasa kupata kwamba int kutumia Maktaba CS50 GetInt 20 00:00:54,470 --> 00:00:59,110 kazi, n anapata GetInt. 21 00:00:59,110 --> 00:01:02,610 Na sasa sisi ni kosa kufanya kitu fulani, lakini tunakwenda wanataka kufanya hivyo 22 00:01:02,610 --> 00:01:04,580 wakati n ni - 23 00:01:04,580 --> 00:01:05,480 nini? - 24 00:01:05,480 --> 00:01:09,370 chini ya 1, kama sisi kweli wanataka sifuri. 25 00:01:09,370 --> 00:01:11,670 >> Hebu kwenda mbele sasa na magazeti nje. 26 00:01:11,670 --> 00:01:17,590 Kama wote ni vizuri, shukrani kwa chanya int, 27 00:01:17,590 --> 00:01:19,360 semicolon, ila faili. 28 00:01:19,360 --> 00:01:21,480 Hebu sasa kukusanya na kukimbia. 29 00:01:21,480 --> 00:01:25,550 >> Kufanya chanya dot slash chanya. 30 00:01:25,550 --> 00:01:27,470 Na sasa mimi nina kuwa ilisababisha kwa chanya int. 31 00:01:27,470 --> 00:01:29,630 Hebu kushirikiana na 1. 32 00:01:29,630 --> 00:01:31,330 Shukrani kwa ajili ya chanya int. 33 00:01:31,330 --> 00:01:33,650 >> Hebu sasa rerun mpango huu na kushirikiana. 34 00:01:33,650 --> 00:01:35,260 Tafadhali nipe chanya int. 35 00:01:35,260 --> 00:01:37,300 Vipi kuhusu hasi 1? 36 00:01:37,300 --> 00:01:37,910 Kuvutia. 37 00:01:37,910 --> 00:01:40,460 mpango tayari reprompted mimi kwa int. 38 00:01:40,460 --> 00:01:43,170 >> Hebu kuwa kidogo zaidi vigumu kwa 0. 39 00:01:43,170 --> 00:01:46,310 Bado si mazuri int, hivyo basi kushirikiana na wakati huu 40 00:01:46,310 --> 00:01:48,280 kutoa, tena, 1. 41 00:01:48,280 --> 00:01:49,990 Shukrani kwa ajili ya chanya int. 42 00:01:49,990 --> 00:01:54,300 >> Sasa ni muhimu kutambua kwamba mimi alitangaza n yangu kutofautiana juu ya line 6, 43 00:01:54,300 --> 00:01:56,510 nje ya do-kitanzi wakati. 44 00:01:56,510 --> 00:02:01,030 Alikuwa na mimi badala alitangaza n ndani ya yangu kufanya-wakati kitanzi, hasa juu, kusema, 45 00:02:01,030 --> 00:02:06,230 mstari wa 10, ambapo mimi pia kupata int kutoka user, kwamba int n ingekuwa tu 46 00:02:06,230 --> 00:02:09,904 kuwepo ndani ya mipaka ya curly braces ambayo kwa sasa ni juu ya 47 00:02:09,904 --> 00:02:12,320 mstari wa 8 na juu ya mstari wa 11. 48 00:02:12,320 --> 00:02:16,570 >> Kwa maneno mengine, n itakuwa scoped kwa ndani ya kitanzi do-wakati. 49 00:02:16,570 --> 00:02:20,390 Lakini tatizo ni kwamba sisi pia wanataka kutumia n katika line 12 50 00:02:20,390 --> 00:02:21,900 ndani ya hali hiyo. 51 00:02:21,900 --> 00:02:26,120 Hivyo hata ingawa haina ili kuangalia pretty, ni sana makusudi kwamba 52 00:02:26,120 --> 00:02:28,210 n ni alitangaza nje kitanzi hii do-wakati. 53 00:02:28,210 --> 00:02:29,838