Codeforces Beta Round #1

A

/*************************************************************************> File Name: A.cpp> Author: opas_chenxin> Mail: 1017370773@qq.com > Created Time: 2016年05月06日 星期五 02时22分23秒    
*************************************************************************/
#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<cmath>
using namespace std;
int main(int argc, char *argv[])
{int n,m,a;while(scanf("%d%d%d",&n,&m,&a) == 3){int d1 = (n+a-1)/a;int d2 = (m+a-1)/a;cout<<1LL*d1*d2<<endl;}return 0;
}

B

/*************************************************************************> File Name: B.cpp> Author: opas_chenxin> Mail: 1017370773@qq.com > Created Time: 2016年05月06日 星期五 20时28分30秒    
*************************************************************************/
#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<cmath>
using namespace std;
const int maxn = 5000000;
char A[maxn];
char B[maxn];
void solve1(int len)
{int a1 = 0;int loc = 0;while(loc<len){if(A[loc] >= 'A' && A[loc] <= 'Z'){a1 = a1 * 26 + A[loc] - 'A' + 1; }else{break;}loc++;}int b1 = 0;while(loc<len){b1 = b1*10 + A[loc] -'0';loc++;}printf("R%dC%d\n",b1,a1);
}
void solve2(int len)
{int b1 = 0;int loc=1;while(loc < len){if(A[loc] == 'C') break;b1=b1*10+A[loc]-'0';loc++;}loc++;int a1 = 0;while(loc < len){a1 = a1 * 10 + A[loc] - '0';loc++;}loc = 0;while(a1>0){int v = a1%26;char c='Z';if(v != 0)c = 'A'+ v - 1;a1 -= c - 'A' + 1;a1 /= 26;B[loc ++] = c;}B[loc]='\0';for(int i = 0; i < loc/2; ++ i){char tem = B[i];B[i] = B[loc-i-1];B[loc - i - 1] = tem;}printf("%s%d\n",B,b1);
}
int main(int argc, char *argv[])
{
//    freopen("in","r",stdin);int cas;scanf("%d",&cas);for(int cc = 1; cc <= cas; ++ cc){scanf("%s",A);int len = strlen(A);int num = 0, per = 0;for(int i = 0; i < len; ++ i){if(A[i] >= 'A' && A[i] <= 'Z'){if(per == 0) {per = 1;num++;}}else{per = 0;}}if(num == 1)solve1(len);else solve2(len);}return 0;
}

C

/*************************************************************************> File Name: C.cpp> Author: opas_chenxin> Mail: 1017370773@qq.com > Created Time: 2016年06月15日 星期三 19时24分06秒    
*************************************************************************/
#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstring>
#include<cmath>
using namespace std;
#define eps 1e-2
#define pi acos(-1.0)
int n,m;
double s,r,S,p;
double x[4],y[4],ang[4],L[4];
double dis(double x1,double y1,double x2,double y2)
{return sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2));
}
double gcd(double a,double b)
{if(a<eps) return b;if(b<eps) return a;return gcd(b,fmod(a,b));
}
int main(int argc, char *argv[])
{//freopen("in","r",stdin);for(int i=0; i<3; ++i){scanf("%lf%lf",&x[i],&y[i]);}for(int i=0; i<3; ++i){L[i]=dis(x[i],y[i],x[(i+1)%3],y[(i+1)%3]);}sort(L,L+3);p=(L[0]+L[1]+L[2])/2;s=sqrt(p*(p-L[0])*(p-L[1])*(p-L[2]));r=L[0]*L[1]*L[2]/(4*s);for(int i=0; i<2;++i)ang[i]=acos(1-L[i]*L[i]/(2*r*r));ang[2]=2*pi-ang[1]-ang[0];double unit=0;for(int i=0; i<3; ++i)unit=gcd(unit,ang[i]);printf("%.6f\n",pi*r*r*sin(unit)/unit);return 0;
}