ADDED   SRM/547-U/1A.cpp
Index: SRM/547-U/1A.cpp
==================================================================
--- SRM/547-U/1A.cpp
+++ SRM/547-U/1A.cpp
@@ -0,0 +1,111 @@
+#include <iostream>
+#include <sstream>
+#include <iomanip>
+#include <vector>
+#include <string>
+#include <map>
+#include <set>
+#include <algorithm>
+#include <numeric>
+#include <iterator>
+#include <functional>
+#include <complex>
+#include <queue>
+#include <stack>
+#include <cmath>
+#include <cassert>
+using namespace std;
+typedef long long LL;
+typedef long double LD;
+typedef complex<LD> CMP;
+
+class Pillars { public:
+	double getExpectedLength(int w, int x, int y)
+	{
+		if(x>y) swap(x,y);
+
+		double e = 0;
+		int num = 1;
+		for(int y_minus_x=1-x; y_minus_x<=y-1; ++y_minus_x) {
+			e += hypot(y_minus_x, w) * num;
+			if(y_minus_x<0)
+				++num;
+			else if(y_minus_x >= y-x)
+				--num;
+		}
+		return e/y/x;
+	}
+};
+
+// BEGIN CUT HERE
+#include <ctime>
+double start_time; string timer()
+ { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
+template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
+ { os << "{ ";
+   for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
+   os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
+void verify_case(const double& Expected, const double& Received) {
+ bool ok = (abs(Expected - Received) < 1e-9);
+ if(ok) cerr << "PASSED" << timer() << endl;  else { cerr << "FAILED" << timer() << endl;
+ cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
+#define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
+#define END	 verify_case(_, Pillars().getExpectedLength(w, x, y));}
+int main(){
+CASE(0)
+	int w = 1; 
+	int x = 1; 
+	int y = 1; 
+	double _ = 1.0; 
+END
+CASE(1)
+	int w = 1; 
+	int x = 5; 
+	int y = 1; 
+	double _ = 2.387132965131785; 
+END
+CASE(1)
+	int w = 1; 
+	int x = 1; 
+	int y = 5; 
+	double _ = 2.387132965131785; 
+END
+CASE(2)
+	int w = 2; 
+	int x = 3; 
+	int y = 15; 
+	double _ = 6.737191281760445; 
+END
+CASE(2)
+	int w = 2; 
+	int x = 15; 
+	int y = 3; 
+	double _ = 6.737191281760445; 
+END
+CASE(3)
+	int w = 10; 
+	int x = 15; 
+	int y = 23; 
+	double _ = 12.988608956320535; 
+END
+CASE(3)
+	int w = 10; 
+	int x = 23; 
+	int y = 15; 
+	double _ = 12.988608956320535; 
+END
+CASE(4)
+	int w = 1000; 
+	int x = 100000; 
+	int y = 100000; 
+	double _ = -1; 
+END
+CASE(5)
+	int w = 1; 
+	int x = 1; 
+	int y = 1; 
+	double _ = 1; 
+END
+
+}
+// END CUT HERE

ADDED   SRM/547-U/1B.cpp
Index: SRM/547-U/1B.cpp
==================================================================
--- SRM/547-U/1B.cpp
+++ SRM/547-U/1B.cpp
@@ -0,0 +1,136 @@
+#include <iostream>
+#include <sstream>
+#include <iomanip>
+#include <vector>
+#include <string>
+#include <map>
+#include <set>
+#include <algorithm>
+#include <numeric>
+#include <iterator>
+#include <functional>
+#include <complex>
+#include <queue>
+#include <stack>
+#include <cmath>
+#include <cassert>
+using namespace std;
+typedef long long LL;
+typedef long double LD;
+typedef complex<LD> CMP;
+
+class RectangularSum { public:
+	long long minimalArea(int height_, int width_, long long S)
+	{
+		LL H = height_;
+		LL W = width_;
+		static const LL INF = 0x7fffffffffffffffLL;
+		LL best = INF;
+
+		vector<LL> divs;
+		for(LL x=1; x*x<=2*S; ++x)
+			if(2*S%x==0) {
+				divs.push_back(x);
+				divs.push_back(2*S/x);
+			}
+	
+		// sum = L1 + (L1 + wX) + (L1 + 2wX) + ... + (L1 + (Y-1)wX)
+		//     = L1*Y + wX(Y-1)Y/2
+		//     = (L1+wX(Y-1)/2) * Y
+		// L1 = p + (p+1) + ... + (p+X-1)
+		//    = p*X + X(X-1)/2
+		//
+		// sum = (p + (X-1)/2 + w(Y-1)/2) * X * Y
+		// 2sum = (2p + X-1 + w(Y-1)) * X * Y
+
+		for(int i=0; i<divs.size(); ++i) {
+			LL Y = divs[i];
+			if(Y<=H)
+			{
+				LL R = (2*S)/Y;
+				for(int j=0; j<divs.size(); ++j) {
+					LL X = divs[j];
+					if(X<=W && R%X == 0)
+					{
+						LL T = R/X;
+						LL twoP = T - (X-1) - W*(Y-1);
+						if( (twoP&1) == 1 )
+							continue;
+						LL P = twoP/2;
+						if( P<0 || H*W<=P )
+							continue;
+						LL x = P%W;
+						LL y = P/W;
+						if( x+X<=W && y+Y<=H ) {
+
+							best = min(best, X*Y);
+						}
+					}
+				}
+			}
+		}
+		return best == INF ? -1 : best;
+	}
+};
+
+// BEGIN CUT HERE
+#include <ctime>
+double start_time; string timer()
+ { ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
+template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
+ { os << "{ ";
+   for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
+   os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
+void verify_case(const long long& Expected, const long long& Received) {
+ bool ok = (Expected == Received);
+ if(ok) cerr << "PASSED" << timer() << endl;  else { cerr << "FAILED" << timer() << endl;
+ cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
+#define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
+#define END	 verify_case(_, RectangularSum().minimalArea(height, width, S));}
+int main(){
+
+CASE(0)
+	int height = 2; 
+	int width = 3; 
+	long long S = 8LL; 
+	long long _ = 4LL; 
+END
+CASE(1)
+	int height = 3; 
+	int width = 3; 
+	long long S = 10LL; 
+	long long _ = -1LL; 
+END
+CASE(2)
+	int height = 3; 
+	int width = 3; 
+	long long S = 36LL; 
+	long long _ = 9LL; 
+END
+CASE(3)
+	int height = 25; 
+	int width = 25; 
+	long long S = 16000LL; 
+	long long _ = 32LL; 
+END
+CASE(4)
+	int height = 1000000; 
+	int width = 1000000; 
+	long long S = 1000000000000LL; 
+	long long _ = 2LL; 
+END
+CASE(5)
+	int height = 1000000; 
+	int width = 1000000; 
+	long long S = 123456789LL; 
+	long long _ = -999LL; 
+END
+CASE(6)
+	int height = 2; 
+	int width = 3; 
+	long long S = 6LL; 
+	long long _ = 4LL; 
+END
+
+}
+// END CUT HERE