Qhov Tseem Ceeb Qhov txawv - Static vs Dynamic Memory Allocation
Hauv kev ua haujlwm, nws yuav tsum khaws cov ntaub ntawv suav. Cov ntaub ntawv no tau muab khaws cia rau hauv lub cim xeeb. Lub cim xeeb qhov chaw rau khaws cov ntaub ntawv hauv computer programming yog hu ua variables. Cov variables muaj ib hom ntaub ntawv tshwj xeeb. Yog li ntawd, lub cim xeeb yog faib los khiav cov kev pab cuam. Kev nco tuaj yeem faib ua ob txoj hauv kev. Lawv yog Static memory allocation thiab Dynamic memory allocation. Hauv kev faib kev nco zoo li qub, thaum lub cim xeeb tau faib nws tsis tuaj yeem hloov pauv. Lub cim xeeb tsis rov siv tau. Tab sis nyob rau hauv dynamic memory allocation, thaum lub cim xeeb faib nws yuav hloov tau. Qhov sib txawv tseem ceeb ntawm kev faib cov cim xeeb zoo li qub thiab lub cim xeeb zoo li qub yog tias nyob rau hauv kev faib lub cim xeeb zoo li qub thaum lub cim xeeb tau muab faib, lub cim xeeb loj yog tsau thaum nyob hauv kev faib lub cim xeeb, thaum lub cim xeeb tau faib, lub cim xeeb loj tuaj yeem hloov pauv.
Kev faib Memory Static yog dab tsi?
Nyob rau hauv kev faib lub cim xeeb zoo li qub, lub cim xeeb faib tau raug kho. Thaum lub cim xeeb tau faib, nws hloov tsis tau. Lub cim xeeb tsis tuaj yeem nce lossis txo qis. Piv txwv li, hauv C hom lus yog tus programmer sau int x, uas txhais tau hais tias qhov sib txawv tuaj yeem khaws tus lej suav. Tus naj npawb ntawm bytes nyob ntawm lub computer. Kuj tseem muaj arrays. E.g. int x [5]; Qhov no x yog ib qho array uas tuaj yeem khaws ib ntu ntawm cov ntaub ntawv uas yog tib hom. Nws tuaj yeem khaws tsib tus lej lej. Nws tsis tuaj yeem khaws ntau tshaj tsib lub ntsiab lus. Hauv Java, ib qho array tuaj yeem tsim tau li, int arr=tshiab int[5]; Cov array 'arr' tuaj yeem khaws 5 qhov tseem ceeb thiab tsis tuaj yeem khaws ntau tshaj qhov ntawd.
Daim duab 01: Memory Allocation Methods
Nyob rau hauv kev faib cov cim xeeb zoo li qub, thaum cov hloov pauv tau faib, lawv nyob ruaj khov. Tom qab qhov pib faib, tus programmer tsis tuaj yeem hloov kho lub cim xeeb. Yog tias tus programmer faib cov array uas tuaj yeem khaws 10 lub ntsiab lus, nws tsis tuaj yeem khaws cov nqi ntau dua li qhov tau teev tseg. Yog tias tus programmer pib faib cov array uas tuaj yeem tuav tau 10 lub ntsiab lus, tab sis tsuas yog xav tau 5 lub ntsiab lus, ces muaj kev nco tsis zoo. Lub cim xeeb ntawd tsis xav tau lawm, tab sis nws kuj tsis tuaj yeem rov siv lub cim xeeb. Kev faib cov cim xeeb zoo li qub tau kho tab sis qhov kev siv tau yooj yim thiab yooj yim, thiab nws kuj ceev ceev.
Dynamic Memory Allocation yog dab tsi?
Qee zaum nws yuav tsum hloov qhov loj ntawm lub cim xeeb. Yog li nco tuaj yeem faib dynamically. Nyob ntawm qhov ntxig thiab tshem tawm ntawm cov ntaub ntawv ntsiab lus, lub cim xeeb tuaj yeem loj hlob lossis ntsws. Nws yog lub npe hu ua dynamic memory allocation.
Hauv C lus, stdlib.h cov ntaub ntawv header, muaj plaub txoj haujlwm rau kev faib lub cim xeeb dynamic. Lawv yog calloc, malloc, realloc thiab dawb. Qhov kev ua haujlwm malloc() faib qhov loj me ntawm bytes thiab xa rov qab tus pointer tsis muaj dab tsi, taw qhia thawj byte ntawm lub cim xeeb faib. Qhov kev ua haujlwm calloc() faib qhov loj me ntawm bytes thiab pib lawv mus rau xoom. Tom qab ntawd rov qab ib tus pointer tsis muaj dab tsi rau lub cim xeeb. Lub free() muaj nuj nqi yog siv los muab faib lub cim xeeb. Thiab realloc muaj nuj nqi tuaj yeem hloov kho lub cim xeeb yav dhau los. Tom qab faib lub cim xeeb siv calloc lossis malloc, lub cim xeeb loj yog tsau, tab sis lawv tuaj yeem nce lossis txo tau siv realloc muaj nuj nqi. Hauv Java, cov ntawv sau tuaj yeem siv rau kev faib lub cim xeeb dynamic.
Qhov txiaj ntsig tseem ceeb ntawm kev faib lub cim xeeb dynamic yog tias nws txuag lub cim xeeb. Tus programmer tuaj yeem faib lub cim xeeb lossis tso lub cim xeeb raws li qhov tsim nyog. Lub cim xeeb tuaj yeem hloov pauv thaum ua tiav thiab tuaj yeem tso lub cim xeeb thaum tsis tas yuav tsum tau ua. Dynamic memory allocation kuj ua tau zoo dua li kev faib kev nco zoo li qub. Ib qho tsis zoo yog qhov kev siv lub cim xeeb dynamic faib yog complex.
Dab tsi yog qhov zoo sib xws ntawm Static thiab Dynamic Memory Allocation?
- Ob leeg yog lub cim xeeb faib cov txheej txheem.
- Ob leeg yuav tsum tau ua los ntawm tus programmer manually.
Dab tsi yog qhov txawv ntawm Static thiab Dynamic Memory Allocation?
Static vs Dynamic Memory Allocation |
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| Static memory allocation is a method of allocating memory, thiab thaum lub cim xeeb faib, nws yog tsau. | Dynamic memory allocation is a method of allocating memory, thiab thaum lub cim xeeb faib, nws hloov tau. |
| Hloov kho | |
| Hauv kev faib lub cim xeeb zoo li qub, nws tsis tuaj yeem hloov pauv tom qab pib faib. | Nyob rau hauv kev faib lub cim xeeb dynamic, lub cim xeeb tuaj yeem txo qis lossis ua kom loj raws li. |
| Kev faib lub cim xeeb zoo ib yam yooj yim rau kev siv. | Dynamic memory allocation is complex to use. |
| Nyob hauv lub cim xeeb zoo li qub, kev faib ua tiav sai dua li kev faib lub cim xeeb. | Nyob rau hauv lub cim xeeb zoo, kev faib ua haujlwm qeeb qeeb dua li kev faib lub cim xeeb zoo li qub. |
| Kev siv Memory | |
| Nyob rau hauv kev faib lub cim xeeb zoo li qub, tsis tuaj yeem rov qab siv lub cim xeeb uas tsis tau siv. | Dynamic memory allocation tso cai rov qab siv lub cim xeeb. Tus programmer tuaj yeem faib ntau lub cim xeeb thaum xav tau. Nws tuaj yeem tso lub cim xeeb thaum tsim nyog. |
Summary – Static vs Dynamic Memory Allocation
Nyob rau hauv programming, Static memory allocation and dynamic memory allocation is two mechanisms for allocating memory. Qhov sib txawv ntawm qhov kev faib khoom zoo li qub thiab dynamic nco yog tias nyob rau hauv static memory allocation thaum lub cim xeeb faib, lub cim xeeb loj yog tsau thaum nyob rau hauv dynamic nco faib, thaum lub cim xeeb faib, lub cim xeeb loj yuav hloov tau. Tus programmer tuaj yeem txiav txim siab seb lub cim xeeb yuav tsum zoo li qub lossis dynamic nyob ntawm daim ntawv thov.
Download the PDF of Static vs Dynamic Memory Allocation
Koj tuaj yeem rub tawm PDF version ntawm kab lus no thiab siv nws rau offline lub hom phiaj raws li daim ntawv ceeb toom. Thov rub tawm PDF version ntawm no: Qhov sib txawv ntawm qhov chaw nyob thiab qhov chaw nco zoo
