Computer Science - 4CP0 PearsonEdexcel

Input/output

Gbogbo ọrọ náà

A program that never asks its user anything, and never saves anything, is not much use. Real programs collect information from the person using them, check that information makes sense before acting on it, and keep a permanent record on disk so the data survives after the program closes. That is what input, validation and file handling give you.

In this lesson you will learn how to accept input from the keyboard and respond to it correctly, how to build validation that rejects impossible or unusable values, and how to read from and write to a text file. Every example is written in Python, one of the languages you can use for the Paper 2 practical programming exam.

Ebumnobi

Understand how to write code that accepts and responds appropriately to user input
Understand the need for, and how to implement, validation
Be able to write code that reads/writes from/to a text file

Akọmọ Ojú-ẹkọ

Every interactive program follows the same pattern: it displays a prompt, waits for the user to type something, does something with that value, and shows a result. In Python that pattern uses two built-in functions you will use constantly: input() to collect what the user typed, and print() to send output to the screen.

Ọ dị na ngwa Green Bridge

Budata ngwa Green Bridge CBT na ekwentị maọbụ kọmputa gị iji nweta akwụkwọ ndụmọdụ zuru oke, ajụjụ mmụta, na ndị ọzọ.

Akwụkwọ ndụmọdụ zuru oke nwere eserese

Onye inyeaka mmụta AI

Mụọ n'ụzọ na-enweghị ịntaneti, oge ọbụla, ebe ọbụla

Budata ngwa ekwentị Budata ngwa kọmputa

Ọ dị na Android, Windows, macOS, na Linux

Ayẹwo Ẹkọ

Ekele diri gi maka imecha ihe karịrị na Input/output. Ugbu a na ị na-enyochakwa isi echiche na echiche ndị dị mkpa, ọ bụ oge iji nwalee ihe ị ma. Ngwa a na-enye ụdị ajụjụ ọmụmụ dị iche iche emebere iji kwado nghọta gị wee nyere gị aka ịmata otú ị ghọtara ihe ndị a kụziri.

Ị ga-ahụ ngwakọta nke ụdị ajụjụ dị iche iche, gụnyere ajụjụ chọrọ ịhọrọ otu n’ime ọtụtụ azịza, ajụjụ chọrọ mkpirisi azịza, na ajụjụ ede ede. A na-arụpụta ajụjụ ọ bụla nke ọma iji nwalee akụkụ dị iche iche nke ihe ọmụma gị na nkà nke ịtụgharị uche.

Jiri akụkụ a nke nyocha ka ohere iji kụziere ihe ị matara banyere isiokwu ahụ ma chọpụta ebe ọ bụla ị nwere ike ịchọ ọmụmụ ihe ọzọ. Ekwela ka nsogbu ọ bụla ị na-eche ihu mee ka ị daa mba; kama, lee ha anya dị ka ohere maka ịzụlite onwe gị na imeziwanye.

What data type does Python's input() function always return? A) Integer B) Float C) String D) Boolean Answer: C
Which file mode adds new content to a file without deleting what is already there? A) "r" B) "w" C) "a" D) "x" Answer: C
A program must reject any exam mark that is not between 0 and 100. What type of validation check is this? A) Presence check B) Range check C) Length check D) Type check Answer: B
Which statement should be used to open a file so that it closes automatically, even if an error occurs? A) import B) try C) with D) def Answer: C
In Python, which method removes the trailing newline character from a line read from a file? A) .split() B) .strip() C) .read() D) .write() Answer: B