ABCD * D = DCBA (Puzzle+Solution)

April 7, 2017 § Leave a comment

The Puzzle

“ABCD * D = DCBA”, Replace every character with a number to make the equation mathematically right.

The Solution using brute-force algorithm

using namespace std;
int main(){
    for(int a=0;a<=9;a++){
        for(int b=0;b<=9;b++)if(a!=b){
            for(int c=0;c<=9;c++)if(a!=c && b!=c){
                for(int d=0;d<=9;d++)if(a!=d && b!=d && c!=d){
                        if((a*1000+b*100+c*10+d)*d == (d*1000+c*100+b*10+a))
                            return cout<<"abcd\n"<<a<<b<<c<<d,0;

    return 0;

The final answer is 1089.


The 6th number is both square and triangular [Puzzle]

March 28, 2017 § Leave a comment


Coffee and Cream problem, My solution

June 21, 2016 § Leave a comment

Here’s the problem from Mr.Honner Blog:

I was recently reminded of an excellent math problem involving mixtures.

Imagine yourself sitting in front of a cup of coffee and a cup of cream.



Suppose you take a spoonful of cream, pour it into the coffee, and stir it up. Now once that’s thoroughly mixed, you take a spoonful of the mixture and pour it back into the cream. Then you mix that up.  After all of this, is there more coffee in the cream, more cream in the coffee, or equal amounts in both?

I encourage you to think about the problem before perusing the several solutions below!

Here’s my solution:
my answer is more cream in the coffee.
my explanation is in the first step the spoonful consisted of pure cream, then the second spoonful from the coffee cup consisted of “cream and coffee” and for each step the spoonful will consist of the mix and impossible it contains pure coffee in any step.
let’s using math…
we will assume that x+n=1; //1 as the size of spoonful.
and will assume that 5 as a cup size.

coffee -> 5cf , cream -> 5cr
cf–>coffee , cr–>cream
-important note-
*the ratio is the origin content/the other content and we’ll  compare ratios.

1st step: 5cr-1cr, 5cf+1cr = 4cr , 5cf + 1cr
2nd step: 4cr+ncf+(x-n)cr=(4+x-n)cr+ncf, 5cf+1cr-ncf-(x-n)cr= (5-n)cf + (1-x+n)cr //General formula
let’s try some cases like n=0.2 , n=0.1 and n=0.6;

1st cup”cr” (ratio) — 2nd cup”cf” (ratio)
(4.6)cr+.8cf (5.75) — (4.8)cf+(1.6)cr (3) // cr > in coffee
(4.8)cr+.1cf (48) — (4.9)cf+(1.8)cr (2.7) // cr > in coffee
(3.8)cr+.6cf (6.3) — (4.4)cf+(1.2)cr (3.7) // cr > in coffee
let’s try n=0.5 🙂
4cr+.5cf (8) — 4.5cf+1cr (4.5) //cr > in coffee, okay that’s great! make sense

Puzzle N.4-10 Level 1

June 1, 2015 § Leave a comment

#Puzzle 💡💡

Which letter completes the puzzle?




Puzzle N.3-3 Level 1

May 28, 2015 § 1 Comment

#Puzzle 💡💡

Which circle replaces the question mark?




Puzzle N.5-15 Level 1

May 27, 2015 § 1 Comment

#Puzzle 💡💡




Puzzle N.2-4 Level 1

May 26, 2015 § 2 Comments

#puzzle 💡💡
Complete it …312312
?= ❓


Puzzle N.1-11 Level 1

May 11, 2015 § Leave a comment

#puzzle 💡💡

?= ❓


2048 ادمان

May 9, 2014 § Leave a comment


2048 مش مجرد رقم بالسهل انك تشوفه ، انا هتكلم فى البوست ده عن لعبة 2048 number puzzle game !
قبل الدخول فى تفاصيل متحكمش على حاجة الا لما تجربها ، فانا هقولك ايه اللعبة دى باختصار وهتلاقى فى اخر البوست لينك تقدر تلعب بيه اللعبة وتجربها 

اللعبة بتتلعب ازاى ؟!
انت بتحرك صف او عمود ولو فى مربعين ليهم نفس الرقم بيتجمعوا فى مربع واحد ، وانت بتحاول تجيب مربع 2048 ، سهلة مش كدة !

اللعبة من ابتكار واحد اسمه gabriel ecirulli ده لينك التعريف بتاعه لو حابب تعرفه اكتر 

موجودة ع Play Store وموجودة ع App Store حملها اكتر من 10M شخص 

بص انا مش هتكلم كتير ع اللعبة بس انت ممكن تجرب ومنصحكش تحملها ع موبايلك 
ده لينك اللعبة جربها 

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