projectEUREKA - a collection of problems, puzzles and trivia

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Showing 10 problems

Problem 260 - Look and say sequence - Solution Verified

Consider the look and say sequence:

1, 11, 21, 1211, 111221, 312211, ....

What is the sum of all digits of the 50th element? ...
Solve it!

11 correct answers, 17 tries, 1 commented solution , 8 solvers: (ffao) (stranac) (guest) (yelly) Alex Velazquez (Alexmula) (bobbygriffin) (yat) (csilviu) (Show all user statistics)

Submitted by Robert Benea (robenea) on May 26 2009 | Discuss

Category programming, Tags look and say sequence

Problem 1028 - French North America - Solution Verified

Which part of North America still belongs to France?
Solve it!

4 correct answers, 36 tries, 1 commented solution , 4 solvers: (lucky99) (csilviu) (Northwolves) (guest) (Show all user statistics)

Submitted by Joe (work) on May 17 2010 | Discuss

Category trivia

Problem 262 - Look and say sequence - variant - Solution Not Verified

Consider the following variant for the look and say sequence:

7
17
1117
3117
132117
31131217
23411217
2213143117

What ...
Solve it!

2 correct answers, 4 tries, 1 commented solution , 2 solvers: (guest) (yat) (Show all user statistics)

Submitted by Robert Benea (robenea) on May 26 2009 | Discuss

Category programming, Tags sequence look and say

Problem 8 - IBM - Solution Verified

This puzzle is about replacing digits (0-9) with letters (ponderthis) where each letter represents a different digit. For example, ...
Solve it!

4 correct answers, 5 tries, 0 commented solutions , 4 solvers: Robert (uzurpatorul) (alvaro) Dan Dima (heartwork) (Moonbeam) (Show all user statistics)

Submitted by Robert Benea (robenea) on February 28 2009 | Discuss

Tags ibm research ponder this

Problem 10 - 100 prisoners - Solution Verified

There are 100 prisoners in solitary cells. There’s a central living room with one light bulb; this
bulb is initially off. No prisoner ...
Solve it!

19 correct answers, 259 tries, 2 commented solutions , 10 solvers: Robert (uzurpatorul) Bogdan Mitu (bogdanm) (yat) (maest) (overbored) (guest) (petrusoroaga) (Moonbeam) (Glarfugus) (Amorydai) (Show all user statistics)

Submitted by Robert Benea (robenea) on March 01 2009 | 1 Comment

Category general, Tags puzzle ibm research

Problem 1037 - Morse - Solution Not Verified

Morse code is a way of encoding character strings using tones of two durations—short and long, separated by gaps. The short tones ...
Solve it!

1 correct answer, 2 tries, 0 commented solutions , 1 solver: (csilviu) (Show all user statistics)

Submitted by (ilduderino) on May 26 2010 | Discuss

Category programming

Problem 274 - Function over positive integers - Solution Not Verified

The set of all positive integers is divided into two disjoint subsets:
{f(1), f(2), f(3), ... } and
{g(1), g(2), g(3), ... }, ...
Solve it!

2 correct answers, 9 tries, 1 commented solution , 2 solvers: (yat) (Northwolves) (Show all user statistics)
Source: IMO like

Submitted by Dan Dima (heartwork) on May 28 2009 | Discuss

Category math

Problem 1042 - fast data structure - Solution Verified

Implement a data structure such that it provides push(), pop() and GetMax() operations on integers (GetMax - returns the max element ...
Solve it!

10 correct answers, 30 tries, 1 commented solution , 9 solvers: (csilviu) (vdineva) (bobbygriffin) (sumant_svce) emily tadena (julyanruby_emily@yahoo.com) Shiela Kathleen Borja (hype17) (guest) (ASHI_ASHIMA) (Tetha) (Show all user statistics)

Submitted by (ilduderino) on May 26 2010 | Discuss

Category programming, Tags interview

Problem 798 - An Every Man For Himself Chess Puzzle - Solution Not Verified

An "Every Man For Himself Chess Puzzle" is a puzzle where each chess piece is unprotected and must not attack a foe nor be attacked ...
Solve it!

0 correct answers, 3 tries, 0 commented solutions

Submitted by (rubenantonio) on December 21 2009 | Discuss

Category logic

Problem 1060 - how many right triangles - Solution Not Verified

How many right triangles, whose sides are all positive whole numbers, have the property that the area is numerically equal to its ...
Solve it!

1 correct answer, 1 try, 2 commented solutions , 1 solver: Mickey Gutman (mgutman) (Show all user statistics)

Submitted by (ilduderino) on June 28 2010 | Discuss

Category math, Tags geometry

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