All language subtitles for In which I solve an EXTREME SUDOKU for Twitter-en

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all right so i received a tweet from kia

seven saying that this extreme sudoku is

annoying i'd like to see what's your

process of solving so i'm going to look

at this this is just a classic sudoku no

weird variant rules today this is just

place the digits 1 through 9 in each row

column and three by three box

with no repeats uh the rules say

with repeats for some reason because i

don't know how to type there we go with

no repeats let's do it that way that's

important

all right so let's take a look at it so

um i mean there's lots of ways to

approach a sudoku one of the things that

i do i think a lot of people do this is

i just sort of

you can look around and see if something

jumps out at you

but i tend to just kind of look at the

ones look at the twos look at the threes

it's not the most efficient way but it

gets it done so

you know we got ones there's gonna be

ones up there

one's in here

so we got a bunch of spots where we can

limit it to three

twos

not seeing anything great with twos

threes

so only a couple of threes in the grid

ah so if we look down here we can't put

a three there and we can't put a three

here and obviously those can't be threes

so this has to be a three

which means there's a three there and a

three down here

okay we only have the one four so that's

not going to do us much good

fives

in there

there there

yeah not much with the fives sixes get

us anything

sixes no

sev ah seven look at this should have

had that right away the sevens here mean

there's a seven up there

and then

ah and down here this seven sees that

this has to be a seven so these are

gonna be six eight nine and there's a

six and an eight right there so that

makes that a nine

okay so we have six and eight in those

and so

to right here this sees one two three

six seven eight nine so it has to be a

four of five

um up here let's see can we do anything

here these are one four five and seven

right here c is a one five and a seven

so this cell sees one two three five six

seven eight nine it has to be a four

so these are one five and seven that one

can't be a seven that one can't be a one

um

all right so

sevens yeah sevens yep okay

we only have the one eight so that's not

super helpful

these are one two four and five

and this one can't be one or five and

this one can't be five so there's a five

in one of these two

and there's a one in one of these two

it's interesting there's something going

on with fives and ones because look at

this one five one five one five

there's some so none of these can be

ones or fives so this

the ones and fives are there

they're in here

there

yeah

that's interesting they're limited the

ones and five seem to have a

interesting connection here and then

fives are here and ones are here

not sure what that tells us though

well so let's look at this row

look at this row where can we put a one

or a five we can't put a one or a five

here

because of the one and five we can't put

it here because of this one five and we

can't put it over here because it's the

same box as the one and the five so

these two

are actually a one five pair now that's

really interesting because if if this is

a 1

then you have a 5 here and down here if

this is a 5 you'd have a 1 here and down

here

and vice versa if this is a 1 you have

ones down here if there's a five you

know fives down here

so the ones and fives are somehow

connected in here it seems like

so what happens if this is a one

this can't be a one this is a one

and if this is a five this is a five

so again whichever one is here is over

here oh and look okay so if this is a

five because of that five it puts a five

there

if this is a one you have a one there

because of that one it puts a one up

here because the one and five over here

as well so whichever one is here

is

is down here and up there

and

and okay right so look at this if this

one right if this is five there's a five

up here we just decided that right but

now you have five here five there you

have to have a five uh in one of these

three which is obviously not there one

of these two but look the one and the

five here rule these out

as well

so if it's the five it's here which puts

a five

right there if it's a one it's here

which puts a one

right there

so whichever digit is here

has to be in one of those

as well as one of these

and is right there these two are the

same digit

let's color those those two are the same

digit now what does that mean i don't

know

but it's something

if it's a five it's down here if it's a

one it's there

ah what that means is right so whichever

one this is if it's five

or one there's a one and a five up here

so whichever one it is

it's here it's up there so

in box five it's got to be down here and

we know it can't be over there so it has

to be one of these two but these are the

same so that one is right there

so

this is either one or five this is the

other one let's make it purple

this is the same as that one these are a

one five pair

these are not one or five that's a seven

gives us five one one

these are ones that's a five

these are not ones okay and we said that

had to be over here because this one

here means that's not a one so now in

this row this has to be a one

which puts a one up there

and

now we can probably get the rest of the

ones yep final one is right there all

right now i'm gonna get rid of the

colors because we don't really need

those anymore let's see can we finish

off the fives now

um five five so there's a five up here

it can't be there so this is five

five that puts a five down here

can't be right there

these two put it in the middle that one

uh five five oh so this is now four

which means that's two and five this is

not five the five goes right there i

can't type

uh that means we've got all the fives

and all the ones all right so

let's see where do we go from there

well these are

two three six and nine these can't be

two or six this can't be three

okay

uh let's look down here

three four

six eight and nine

this one isn't six these can't be three

or four

so that's six eight and nine these two

are three and four

which means these are

six eight and nine these are two and

seven

this one can't be nine because the nine

up there

what do we need up here two four seven

eight nine these can't be seven or nine

these can't be four

or seven

it's not super helpful though all right

there's gotta be a spot where oh twos

look over here in this box where can you

put a two you can't put it here

or there this is a two which means these

are not twos

uh that puts a two up there

two's over here oh this two look two set

the two is looking at that two seven so

that's a seven that's two

now this is a two because of these

these are not twos

there's a two up there

ah this is two

in the box here because of these

ruling out all that

which means these are not twos so the

two in box two is there puts two up

there and now i think we have all the

twos

very good

um

let's look across the top here so we

need

four six and eight

this one can't be six so we've got a

four eight pair that puts the six over

here means that's not a six

these are

three four seven and eight

uh these are not four or seven

so that gives us all that the three

eight pair means this is not an eight

um

all right let's just keep going over

here this is

three eight nine this can't be eight

nine these are

four six seven and eight these can't be

four or seven

these can't be six or eight this one

can't be seven

three six eight nine across there

this one can't be six so it's three

eight nine

ah right here

this

uh

has to be six or nine

but there's a six there so this is the

nine this is six an eight and nine that

makes this a six and a three

and

this is an eight and a four and a seven

which makes this uh four i believe that

four will give us the three and the four

down here

uh the six here gives us nine

those are not this is now a three six

pair so that's not a six so so that's an

eight and a six

the nine there gives us the eight

four

eight

that eight is going to give us the nine

uh the nine here this is not a nine

that's six

three six

uh these are not

four or eight so that's a seven nine

pair this is not a three

so these are three and nine and the

three down here will give us the order

of those that 8 gives us the 6 and the

8.

these are

3 and 4 these are

6 and 9. that's 6 gives us 9 and 6 the 9

and nine the seven gives us the four and

the seven the four gives us the three

and the four and the three gives us the

eight and the three

there we go looks good to me timer stops

so there we go

so that took uh exactly 13 minutes

so pretty cool so there was a little bit

of a tricky part right there with the

ones and the fives um

so one thing that can really help let's

see let me back up to

that point for a second

so one thing to think about is so

since these ones and fives were kind of

grouped together

um it seemed like they were kind of

working as a pair and so

what i noticed was this row five

you could rule ones and fives out of

a lot of spots and so once we had our

one five pair

um sometimes it can help to color things

and say well this one is

you know yellow and so this one or green

i think i think that's green

this one's green this one's purple and

then you can kind of go around the grid

and figure out

um this didn't take too sometimes you

have to color like

a bunch of places and say well green

green green green green and then purple

purple purple purple you know um and

essentially if you find out uh let's see

so we were right here

once we know that this is green

it forced this to be green and this had

to be purple and since you have purple

and green

you can rule out that one five from

any other cell that both of those see

so for example we could also rule one

and five out of these because they see

green in the box and purple in the

column

so you couldn't put a one or a five in

either of these cells

so they also see purple and green both

in the column but

um so that gave us the seven there and

that was what unlocked the rest of the

puzzle so

yeah that was a little bit tricky in the

middle there so let me know what you

thought of this sudoku thank you for

that suggestion kia and i'll see you

again soon with some more puzzles thanks

bye