i++<\/code>.<\/p>\n\n\n\nNh\u01b0ng ri\u00eang v\u1edbi C++<\/code>, s\u1ef1 ch\u00eanh l\u1ec7ch c\u00f3 th\u1ec3 l\u00e0 \u0111\u00e1ng k\u1ec3 trong m\u1ed9t s\u1ed1 tr\u01b0\u1eddng h\u1ee3p. C\u1ee5 th\u1ec3 l\u00e0 v\u1edbi user-defined type, t\u1ee9c l\u00e0 class<\/code> b\u1ea1n t\u1ea1o ra, v\u00ec operator++()<\/code> l\u00e0 m\u1ed9t h\u00e0m v\u00e0 compiler kh\u00f4ng bi\u1ebft l\u00e0m c\u00e1ch n\u00e0o \u0111\u1ec3 optimize vi\u1ec7c t\u1ea1o ra c\u00e1i temp object trong \u0111\u00f3 c\u1ea3. Sao n\u00f3 bi\u1ebft \u0111\u01b0\u1ee3c b\u1ea1n define c\u00e1i g\u00ec v\u00e0 s\u1ebd b\u1ef1 c\u1ee1 n\u00e0o trong class.<\/p>\n\n\n\nV\u1eady n\u00ean x\u00e0i c\u00e1i n\u00e0o trong v\u00f2ng for<\/code>?<\/h2>\n\n\n\nRi\u00eang \u0111\u1ed1i v\u1edbi m\u00ecnh th\u00ec ++i<\/code> \u0111\u00e3 tr\u1edf th\u00e0nh m\u1ed9t convention b\u1ea5t th\u00e0nh v\u0103n r\u1ed3i. D\u00f9 chi\u1ebfn project n\u00e0o m\u00ecnh c\u0169ng x\u00e0i n\u00f3 m\u00e0 ch\u1ea3 quan t\u00e2m performance g\u00ec cho m\u1ec7t \u00f3c. R\u1ea5t nhi\u1ec1u guru trong gi\u1edbi coder \u0111\u1ec1u \u0111\u01b0a ra l\u1eddi khuy\u00ean:<\/p>\n\n\n\nIN ANY CASE, FOLLOW THE GUIDELINE \u201cPREFER ++I OVER I++\u201d AND YOU WON\u2019T GO WRONG<\/p>\n\n\n\n
(from many Khuy\u1ebft Danh)<\/p>\n\n\n\n
M\u1ed9t ch\u00fat v\u1ec1 side effect v\u00e0 undefined behavior<\/h2>\n\n\n\nV\u00ed d\u1ee5 1:<\/h3>\n\n\n\n![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2020\/01\/\u1ea2nh-ch\u1ee5p-M\u00e0n-h\u00ecnh-2020-01-11-l\u00fac-01.19.40.png\")
<\/figure>\n\n\n\nV\u00ed d\u1ee5 2:<\/h3>\n\n\n\n![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2020\/01\/\u1ea2nh-ch\u1ee5p-M\u00e0n-h\u00ecnh-2020-01-11-l\u00fac-01.19.08.png\")
<\/figure>\n\n\n\nM\u00ecnh s\u1ebd kh\u00f4ng gi\u1ea3i th\u00edch \u201cSide effect hay UB l\u00e0 g\u00ec?\u201d \u1edf \u0111\u00e2y. Topic n\u00e0y c\u0169ng kh\u00e1 th\u00fa v\u1ecb n\u00ean m\u00ecnh s\u1ebd vi\u1ebft ri\u00eang m\u1ed9t b\u00e0i v\u1ec1 n\u00f3. Nh\u01b0ng qua hai v\u00ed d\u1ee5 tr\u00ean ch\u1eafc b\u1ea1n c\u0169ng th\u1ea5y \u0111\u01b0\u1ee3c s\u1ef1 nguy hi\u1ec3m c\u1ee7a ch\u00fang, n\u1ebfu ph\u00e9p g\u00e1n th\u1ee9 nh\u1ea5t \u1edf v\u00ed d\u1ee5 2 m\u00e0 trong v\u00f2ng l\u1eb7p n\u1eefa th\u00ec .<\/p>\n\n\n\n![\"\ud83d\ude28\"\/](\"https:\/\/s.w.org\/images\/core\/emoji\/11.2.0\/svg\/1f628.svg\")
<\/figure>\n\n\n\nH\u1eb9n g\u1eb7p c\u00e1c b\u1ea1n \u1edf nh\u1eefng b\u00e0i vi\u1ebft sau!2<\/p>\n","protected":false},"excerpt":{"rendered":"
\u0110i\u1ec3m kh\u00e1c bi\u1ec7t Kh\u00e1c bi\u1ec7t c\u01a1 b\u1ea3n n\u00e0y \u00e1p d\u1ee5ng cho h\u1ea7u h\u1ebft c\u00e1c ng\u00f4n ng\u1eef v\u00e0 compiler hi\u1ec7n nay. ++i t\u0103ng gi\u00e1 tr\u1ecb c\u1ee7a i l\u00ean 1 v\u00e0 tr\u1ea3 v\u1ec1 gi\u00e1 tr\u1ecb m\u1edbi \u0111\u00f3.i++ c\u0169ng t\u01b0\u01a1ng t\u1ef1 nh\u01b0ng gi\u00e1 tr\u1ecb tr\u1ea3 v\u1ec1 l\u00e0 gi\u00e1 tr\u1ecb ban \u0111\u1ea7u c\u1ee7a i tr\u01b0\u1edbc khi \u0111\u01b0\u1ee3c t\u0103ng l\u00ean 1. M\u1ed9t \u0111i\u1ec3m \u0111\u00e1ng l\u01b0u \u00fd […]<\/p>\n","protected":false},"author":12,"featured_media":45375,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false,"tdm_status":"","tdm_grid_status":""},"categories":[1651],"tags":[],"yoast_head":"\n
i++ v\u00e0 ++i<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/lop12.edu.vn\/i-va-i\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"i++ v\u00e0 ++i\" \/>\n<meta property=\"og:description\" content=\"\u0110i\u1ec3m kh\u00e1c bi\u1ec7t Kh\u00e1c bi\u1ec7t c\u01a1 b\u1ea3n n\u00e0y \u00e1p d\u1ee5ng cho h\u1ea7u h\u1ebft c\u00e1c ng\u00f4n ng\u1eef v\u00e0 compiler hi\u1ec7n nay. ++i t\u0103ng gi\u00e1 tr\u1ecb c\u1ee7a i l\u00ean 1 v\u00e0 tr\u1ea3 v\u1ec1 gi\u00e1 tr\u1ecb m\u1edbi \u0111\u00f3.i++ c\u0169ng t\u01b0\u01a1ng t\u1ef1 nh\u01b0ng gi\u00e1 tr\u1ecb tr\u1ea3 v\u1ec1 l\u00e0 gi\u00e1 tr\u1ecb ban \u0111\u1ea7u c\u1ee7a i tr\u01b0\u1edbc khi \u0111\u01b0\u1ee3c t\u0103ng l\u00ean 1. 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![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2020\/01\/\u1ea2nh-ch\u1ee5p-M\u00e0n-h\u00ecnh-2020-01-11-l\u00fac-01.20.43.png\")
<\/figure>\n\n\n\n![\"\"](\"https:\/\/lop12.edu.vn\/wp-content\/uploads\/2020\/01\/\u1ea2nh-ch\u1ee5p-M\u00e0n-h\u00ecnh-2020-01-11-l\u00fac-01.20.16.png\")
<\/figure>\n\n\n\n