1 00:00:00,000 --> 00:00:00,620 2 00:00:00,620 --> 00:00:03,140 >> DAVID J. Malan: Hebu kuandika mpango kwamba humshauri mtumiaji kwa kamba na 3 00:00:03,140 --> 00:00:07,210 kisha kuendelea na magazeti kamba kwamba tabia kwa tabia moja kwa kila mstari. 4 00:00:07,210 --> 00:00:10,570 Sasa katika siku za nyuma, tunataka wamefanya hivyo pengine kwa Mabano ya mraba nukuu, 5 00:00:10,570 --> 00:00:13,680 ufanisi kutibu string ni safu ya wahusika. 6 00:00:13,680 --> 00:00:17,200 >> Lakini wakati huu, hebu badala ya kutibu kamba kwa nini kweli ni, a 7 00:00:17,200 --> 00:00:18,770 pointer au anwani. 8 00:00:18,770 --> 00:00:22,420 Hasa, barua pepe ya tabia, kweli pepe ya 9 00:00:22,420 --> 00:00:25,740 tabia ya kwanza, katika mlolongo wa wahusika kuwa sisi pamoja kujua 10 00:00:25,740 --> 00:00:26,860 kama kamba. 11 00:00:26,860 --> 00:00:30,740 >> Hebu kwanza kutangaza kamba kwa nini kweli ni, char *. 12 00:00:30,740 --> 00:00:31,770 Na tutaweza kuiita s. 13 00:00:31,770 --> 00:00:34,670 Na kisha hawawajui kurudi thamani ya kupata kamba. 14 00:00:34,670 --> 00:00:36,380 >> Hebu ijayo kufanya baadhi ya kuangalia makosa. 15 00:00:36,380 --> 00:00:42,920 Kama s ni null, hebu mara moja kurudi hivyo kwamba sisi si ajali 16 00:00:42,920 --> 00:00:45,630 dereference kwamba null pointer. 17 00:00:45,630 --> 00:00:49,750 >> Next, hebu iterate juu ya wahusika katika s kama ifuatavyo. 18 00:00:49,750 --> 00:00:52,390 Kwa int, i anapata 0. 19 00:00:52,390 --> 00:00:55,890 n sawa na kamba urefu wa s. 20 00:00:55,890 --> 00:00:58,050 Je, hii muda mrefu kama i ni chini ya n. 21 00:00:58,050 --> 00:01:00,690 Na juu ya kila iteration, nyongeza i. 22 00:01:00,690 --> 00:01:02,710 >> Na nini tunataka kufanya juu ya kila iteration? 23 00:01:02,710 --> 00:01:06,180 Hebu sasa magazeti nje juu ya kila iteration tabia moja 24 00:01:06,180 --> 00:01:07,910 ikifuatiwa na mstari mpya. 25 00:01:07,910 --> 00:01:10,010 Naam, ni nini tabia ya kufanya tunataka magazeti? 26 00:01:10,010 --> 00:01:16,850 Napendekeza kwamba sisi kwenda anwani kwamba ni sawa na Jumla ya s pamoja na i. 27 00:01:16,850 --> 00:01:18,390 >> Sasa, kwa nini kuwa usemi? 28 00:01:18,390 --> 00:01:22,130 Naam, kukumbuka kuwa kuhifadhiwa katika s ni barua pepe ya tabia ya kwanza 29 00:01:22,130 --> 00:01:23,490 katika kamba yetu, s. 30 00:01:23,490 --> 00:01:27,470 Wakati huo huo, i ni kuwa incremented juu ya kila iteration ili kuanza saa 0, 31 00:01:27,470 --> 00:01:29,590 kisha huenda kwa 1, kisha huenda kwa 2. 32 00:01:29,590 --> 00:01:33,870 >> Hivyo kwa maneno mengine, s pamoja na i ufanisi inawakilisha ya barua pepe ya 33 00:01:33,870 --> 00:01:35,990 i-th tabia katika s. 34 00:01:35,990 --> 00:01:40,830 Hivyo kama sisi kwenda kwa anwani hiyo kwa njia ya * Operator, tutaweza kuwa na kwenda 35 00:01:40,830 --> 00:01:42,650 i-th tabia katika kamba. 36 00:01:42,650 --> 00:01:45,700 Na kwamba thamani ambayo itakuwa badala ya placeholder yetu, 37 00:01:45,700 --> 00:01:46,840 asilimia C. 38 00:01:46,840 --> 00:01:47,840 >> Hebu kuthibitisha kama sana. 39 00:01:47,840 --> 00:01:51,720 Hebu kuokoa, kukusanya, na kuendesha mpango huu. 40 00:01:51,720 --> 00:01:55,990 Kufanya kuyatumia, kuyatumia slash dot. 41 00:01:55,990 --> 00:01:58,780 Na sasa mimi nitakupa ni kamba kama hello. 42 00:01:58,780 --> 00:01:59,600 Kuingia. 43 00:01:59,600 --> 00:02:03,770 >> Na hakika, naona H-E-L-L-O, na kila char juu ya line yake mwenyewe. 44 00:02:03,770 --> 00:02:05,410