The problem: ———- The sequence of triangle numbers is generated by adding the natural numbers. So the 7th triangle number would be 1 + 2 + 3 + 4 + 5 + 6 + 7 = 28. The first ten terms would be: 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, … Let […]
Here’s the problem: ————- Given the list of numbers, you are to sort them in non decreasing order. Input t – the number of numbers in list, then t lines follow [t
You can see the original problem here: ———– In the 2020 grid below, four numbers along a diagonal line have been marked in red. 08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08 49 49 99 40 17 81 18 57 60 87 17 […]
Still practicing for Facebook Hacker Cup 2013: ———- The captain of the ship TITANIC is a little …. off the track. He needs to select the crew for the ship. But everyone seems to be eligible. So to test their intelligence, he plays a game. The contestants have to stand in a line. They are […]
Not the most challenging one, but still: The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. Find the sum of all the primes below two million. My Solution #include <stdio.h> #include <math.h> int isPrime(num){ int i; if (num==2) return 1; for (i=2;i<sqrt(num)+1;i++){ if (num%i==0) return 0; } […]
Here’s an interesting problem from CodeChef.com: ——– You are asked to calculate factorials of some small positive integers. Input An integer t, 1
The problem: A Pythagorean triplet is a set of three natural numbers, a b c, for which, a2 + b2 = c2 For example, 32 + 42 = 9 + 16 = 25 = 52. There exists exactly one Pythagorean triplet for which a + b + c = 1000. Find the product abc. My […]
Facebook Hacker Cup 2013 is coming up, so I started solving some problems on CodeChef.com to warm up. Here’s one of them: ——————– The most important part of a GSM network is so called Base Transceiver Station (BTS). These transceivers form the areas called cells (this term gave the name to the cellular phone) and […]
This is coming from GitHub: L1 cache reference 0.5 ns Branch mispredict 5 ns L2 cache reference 7 ns 14x L1 cache Mutex lock/unlock 25 ns Main memory reference 100 ns 20x L2 cache, 200x L1 cache Compress 1K bytes with Zippy 3,000 ns Send 1K bytes over 1 Gbps network 10,000 ns 0.01 ms SSD random read 150,000 ns Read […]
Here’s another problem that appeared on the 2011 Google Code Jam: You are selling beautiful geometric pictures. Each one consists of 1×1 square tiles arranged into a non-overlapping grid. For example: .##.. .#### .#### .##.. Blue tiles are represented by ‘#’ characters, and white tiles are represented by ‘.’ characters. You do not use other […]