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**Hazique35** Hello, I am really confused on this problem on projecteuler. Its so annoying!!! And its only problem 3! Im using C++ and I am really confused on how to find a technique to find whether a number is prime. My method at the moment is increasing the number that the number I am dividing it by. (600851475143). This method isnt working because I cant really test to see whether a number has more than one decimal point. (Like when 600851475143 / 3. I can use a floating point number because it cannot fit a number that big. Also rounding in C++ isnt that accurate.) Heres an example of some code that I use.

for (int i=0; i <99999; i++);

//code to divide number

Sorry if this isnt that clear... I just need some hints to push me in the right direction.

Thanks!