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Introduction

Competitive Programming is all about “Given well-known Computer Science (CS) problems, solve them as quickly as possible! “.

Type Code Faster.
- 55-65 wpm is decent speed.
Quickly Identify Problem Types.
Do Algorithm Analysis.
- Anything of order of O(n log n) is accepted solutions in most cases.
Master Programming Languages.
- CPP is preferred but some library of Java can be useful for e. g. Big Int
Master the Art of Testing Code.
- Use diff in Unix to check for difference in i/o.
- for multiple case input include same i/p again to check for avoiding reset variable errors.
- Always check corner cases, large cases.
Practice and More Practice.

Background Story/problem description
- for easy problem’s story appear to be deceptive to make it hard.
- hard problems are already hard but explained carefully.
I/O Description.
Samples for I/O.

int TC,a,b;
scanf("%d",&TC);
while(TC--){
    scanf("%d %d",&a,&b);
    printf("%d\n",a+b);
}

Variable # of i/o

int k, ans v;
while (scanf("%d",&k) != EOF){
	ans=0;
    while(k--){ scanf("%d",&v); ans +=v}
    printf("%d\n", ans);
}

These are simply problems that can’t be classified anywhere easily.

But a broad categorization is:

Starred Problems UVa

UVa 11172 - Relational Operators * (ad hoc, very easy, one liner)

UVa 11498 - Division of Nlogonia * (just use if-else statements)

UVa 11727 - Cost Cutting * (sort the 3 numbers and get the median)

UVa 10114 - Loansome Car Buyer * (just simulate the process)

UVa 11559 - Event Planning * (one linear pass)

UVa 11799 - Horror Dash * (one linear scan to find the max value)

UVa 00573 - The Snail * (simulation, beware of boundary cases!)

UVa 10141 - Request for Proposal * (solvable with one linear scan)

UVa 11507 - Bender B. Rodriguez … * (simulation, if-else)

UVa 00462 - Bridge Hand Evaluator (simulation; card)

UVa 10646 - What is the Card? (shuffle cards with some rule and then get certain card)

UVa 12247 - Jollo (interesting card game; simple, but requires good logic to get all test cases correct)

UVa 00278 - Chess (ad hoc, chess, closed form formula exists)

UVa 00696 - How Many Knights (ad hoc, chess)

UVa 10284 - Chessboard in FEN (FEN = Forsyth-Edwards Notation is a standard notation for describing board positions in a chess game)

UVa 00156 - Ananagram (easier with algorithm::sort)

UVa 00195 - Anagram (easier with algorithm::next permutation)

UVa 00454 - Anagrams (anagram)

UVa 00401 - Palindromes (simple palindrome check)

UVa 10945 - Mother Bear (palindrome)

UVa 11221 - Magic Square Palindrome (we deal with a matrix)

UVa 00579 - Clock Hands (ad hoc, time)

UVa 00893 - Y3K (use Java Gregorian Calendar; similar to UVa 11356)

UVa 11947 - Cancer or Scorpio (easier with Java Gregorian Calendar)