10070 - Leap Year or Not Leap Year and …, uva

#include<iostream>
#include<cstdio>
#include<cstdlib>
#define db(a) cout << #a << " = " << a << endl
using namespace std;
string linea;
int n = 0;
bool esbisiesto() {
 bool fin = false;
 int num = 0, t = 1;
 for (int i = 0; i < 4 && !fin; i++) {
  if (i >= n) {
   fin = true;
   continue;
  }
  num = t * (linea[n - i - 1] - 48) + num;
  t *= 10;
 }
 //db(num);
 return (num % 4 == 0 && num % 100 != 0) or (num % 400 == 0);
}
int main() {
 bool por3, por5, por11, bisiesto, first = true;
 while (cin >> linea) {
  if (!first) puts("");
  else first = false;
  n = linea.size();
  bisiesto = esbisiesto();
  int suma11 = 0;
  int suma3 = 0;
  for (int i = 0; i < n; i++) {
   suma3 += linea[i] - 48;
   if (i % 2) suma11 += linea[i] - 48;
   else suma11 -= linea[i] - 48;
  }
  por3 = (suma3 % 3 == 0);
  por5 = (linea[n - 1] - 48) % 5 == 0;
  por11 = suma11 % 11 == 0;
  if (bisiesto) puts("This is leap year.");
  if (por3 && por5) puts("This is huluculu festival year.");
  if (por5 && por11 && bisiesto) puts("This is bulukulu festival year.");
  if (!bisiesto && !(por3 && por5) && !(por5 && por11 && bisiesto))
   puts("This is an ordinary year.");
 }
 return 0;
}

750 - 8 Queens Chess Problem , uva

#include<iostream>
#include<cmath>
#include<cstdio>
#include<cstring>
using namespace std;
int x[9], a, b, cont = 0;
bool place(int queen, int row) {
 for (int prev = 1; prev < queen; prev++)
  if (x[prev] == row or abs(x[prev] - row) == abs(prev - queen))
   return false;
 return true;
}
void Nqueen(int queen) {
 if (queen == 9) {
  if (x[b] == a) {
   printf("%2d      %d",++cont, x[1]);
   for (int i = 2; i <= 8; i++) {
    printf(" %d", x[i]);
   }
   puts("");
  }
 }
 else {
  for (int row = 1; row <= 8; row++) {
   if (place(queen, row)) {
    x[queen] = row;
    Nqueen(queen + 1);
   }
  }
 }
}
int main() {
 int t;
 scanf("%d", &t);
 while (t--) {
  scanf("%d %d", &a, &b);
  memset(x, 0, sizeof x);
  cont = 0;
  printf("SOLN       COLUMN\n");
  printf(" #      1 2 3 4 5 6 7 8\n\n");
  Nqueen(1);
  if (t) puts("");
 }
 return 0;
}

11988 - Broken Keyboard (a.k.a. Beiju Text), uva

#include<iostream>
#include<cstdio>
#include<deque>
#define db(a) cout << #a << " = " << a << endl
using namespace std;
deque<string> deq;
void insert(bool pos, string &s) {
 if (pos) deq.push_back(s);
 else deq.push_front(s);
 s = "";
}
int main() {
 string aux;
 bool end = true;
 char c;
 while (c = getchar()) {
  if (c == EOF) break;
  if (c == '\n') {
   insert(end, aux);
   while (deq.size()) { 
    printf("%s", deq.front().c_str());
    deq.pop_front();
   }
   printf("\n");
   deq.clear();
   aux = "";
   end = true;
  }
  else
   if (c == '[') {
    if (aux != "") {
     insert(end, aux);
    }
    end = false;
   }
   else
    if (c == ']') {
     if (aux != "") insert(end, aux);
     end = true;
    }
    else aux += c;
 }
 return 0;
}

374 - Big Mod , uva

#include<iostream>
#include<ctime>
#include<cstring>
#include<cstdio>
#define mod 131071
#define db(a) cout << #a << " = " << a << endl
#define db2(a, b) cout << #a << " = " << a << " " << #b << " = " << b << endl
using namespace std;
int m;
int power(int n, int p) {
 if (p == 0) return 1;
 if (p == 1) return n;
 if (p & 1) {
  return ((n % m)  * (power(((n % m) * (n % m)) % m, (p - 1) / 2) % m)) % m;
 }
 else {
  return power(((n % m) * (n % m))% m, p / 2);
 }
}
int main() {
 int b, p;
 while (cin >> b >> p >> m) {
  cout << power(b, p) << endl;
 }
 return 0;
}

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10176 - Ocean Deep - Make it shallow , uva

#include<iostream>
#include<cstring>
#include<cstdio>
#define mod 131071
#define db(a) cout << #a << " = " << a << endl
#define db2(a, b) cout << #a << " = " << a << " " << #b << " = " << b << endl
using namespace std;
int main() {
	string binario = "", leido;
	while (cin >> leido) {
		int len = leido.size();
		if (leido[len - 1] == '#') {
			int res = 0;
			binario += leido.substr(0, len - 1);
			int total = binario.size();
			int p = 1;
			for (int i = total - 1; i >= 0; i--) {
				res += (binario[i] - '0') * p;
				res %= mod;
				p *= 2;
				p %= mod;
			}
			if (res == 0) puts("YES");
			else puts("NO");
			binario = "";
		}
		else binario += leido;
	}
	return 0;
}