How do you write a program to check the mistakes in paragraph?

Answer 1

This is no mean feat; actually no spell-checker / grammar-checker does a perfect job. Something simple you could do is just to check whether each word is in a dictionary. The data structures you use will depend on the programming language chosen, but having your dictionary in an array would definitely be slow - you may want to use something like a hashtable or a binary tree instead. However, an array can work for a proof of concept.

If you write your program this way, something like an "Ode to the Spelling Checker" should pass without errors - although it is full of errors. The "Ode to the Spelling Checker" uses words that are in the dictionary - but the wrong word in each case, for example "eye" instead if "I", and "tolled" instead of "told". I paste a copy of the Ode here, for your easy reference - you'll have to read it out loud to make sense out of it!

Eye halve a spelling chequer

It came with my pea sea

It plainly marques four my revue

Miss steaks eye kin knot sea.

Eye strike a quay and type a word

And weight four it two say

Weather eye am wrong oar write

It shows me strait a weigh.

As soon as a mist ache is maid

It nose bee fore two long

And eye can put the error rite

It's rare lea ever wrong.

Eye have run this poem threw it

I am shore your pleased two no

It's letter perfect awl the weigh

My chequer tolled me sew.