Problem #93 concerns the values that can be obtained by evaluating arithmetic expressions with specific sets of digits. The question reads: Project Euler Problem 93: Arithmetic expressions By using each of the digits from the set, {1, 2, 3, 4}, exactly once, and making use of the four arithmetic operations (+, −, *, /) and …
Tag Archives: Project Euler
Project Euler Problem #92
Problem #92 concerns the results when numbers are repeatedly replaced by the square of their digits. The question reads: Project Euler Problem 92: Square digit chains A number chain is created by continuously adding the square of the digits in a number to form a new number until it has been seen before. For example, …
Project Euler Problem #91
Problem #91 concerns right triangles whose vertices lie on lattice points. The question reads: My solution for this problem involves a bit of brute force. Here’s my solution: Solution #1: Brute Force Casework Approach We have several cases to consider. The first is if the right angle is either at the origin or on one …
Project Euler Problem #90
Problem #90 concerns pairs of dice that can be rearranged to form all of the 2-digit square numbers. The question reads: My solution for this problem is very brute force-heavy, so I may come back to this problem to look for a more efficient solution. Here is my solution: Solution #1: Brute Force Approach We …
Project Euler Problem #89
Problem #89 concerns the number of characters in Roman numerals. The question reads: Project Euler Problem 89: Roman numerals For a number written in Roman numerals to be considered valid there are basic rules which must be followed. Even though the rules allow some numbers to be expressed in more than one way there is …
Project Euler Problem #88
Problem #88 concerns numbers which can be expressed as both the sum and the product of the numbers in the same set of numbers. The question reads: Project Euler Problem 88: Product-sum numbers A natural number, N, that can be written as the sum and product of a given set of at least two natural …
Project Euler Problem #87
Problem #87 concerns numbers which can be written as the sum of a perfect square, a perfect cube, and a perfect fourth power of prime numbers. The question reads: Project Euler Problem 87: Prime power triples The smallest number expressible as the sum of a prime square, prime cube, and prime fourth power is 28. …
Project Euler Problem #86
Problem #86 concerns the surface area diagonal of rectangular prisms. The question reads: My solution for this problem definitely falls into the category of brute force. Here is my solution: Solution #1: Brute Force Approach Let F(M) be the number of cuboids with this property ignoring rotations with dimensions less than or equal to M. …
Project Euler Problem #85
Problem #85 concerns finding the number of rectangles with sides along a lattice grid. The question reads: This problem is very well known among those who participate in math competitions. Here is my solution: Solution #1: Combinatorial Approach We can observe that in a grid with m horizontal lines and n vertical lines, any rectangle …
Project Euler Problem #84
Problem #84 concerns simulations of the game Monopoly. The question reads: I apologize for not embedding this problem in WordPress. I felt it would be much simpler if I just added a screenshot due to the long list of instructions. Regardless, this is one of the more intimidating early questions of Project Euler. My solution …
The Inner Machinations of Walker 