【openjudge 计算概论（A）】[基础编程练习（运算成分）]

01:鸡尾酒疗法

#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
const double eps=0.05;
int n,x,y;
int main()
{
	scanf("%d%d%d",&n,&x,&y);
	double p=(double)y/x;
	for(int i=1;i<n;++i)
	 {
	 	int x,y;
	 	scanf("%d%d",&x,&y);
	 	double sum=(double)y/x;
	 	if(sum-p>eps) printf("better\n");
	 	 else 
	 	  if(p-sum>eps) printf("worse\n");
	 	   else printf("same\n");
	 }
	return 0;
}

02:求出e的值

#include<cstdio>
#include<cstring>
#include<algorithm>
#define ll long long
using namespace std;
ll mi[20];
int n;
int main()
{
	int i,j;
	scanf("%d",&n);
	mi[1]=1;
	for(i=2;i<=n;++i) mi[i]=mi[i-1]*i;
	double ans=1;
	for(i=1;i<=n;++i) ans+=(double)1/mi[i];
	printf("%.10lf\n",ans);
	return 0;
}

03:球弹跳高度的计算（等比数列）

#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
double ans,n;
int main()
{
	int i;
	scanf("%lf",&n);
	ans=n;
	i=9;
	double last=n;
	while(i--)
	 {
	 	ans+=n;
	 	n/=2; 
	 }
	n/=2;
	printf("%g %g\n",ans,n);
	return 0;
}

04:求分数序列和

#include<cstdio>
using namespace std;
double ans,a[1100],b[1100];
int n;
int main()
{
	scanf("%d",&n);
	a[1]=2.0; a[2]=3.0;
	b[1]=1.0; b[2]=2.0;
	for(int i=3;i<=n;++i) a[i]=a[i-1]+a[i-2],b[i]=b[i-1]+b[i-2];
	for(int i=1;i<=n;++i) ans+=(a[i]/b[i]);
	printf("%.4lf\n",ans);
	return 0;
}

06:角谷猜想

#include<cstdio>
#include<cstring>
#include<iostream>
using namespace std;
int x;
void pract(int x)
{
    if(x==1)
      {printf("End\n"); return;}
    if (x%2) 
       {int a=x*3+1; printf("%d*3+1=%d\n",x,a); pract(a);}
     else 
       {int a=x/2; printf("%d/2=%d\n",x,a); pract(a);}
    return;
}
int main()
{
 scanf("%d",&x);
 pract(x);
 return 0;
}

07:分数求和

#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
int fm[20],fz[20],n,lcm,sum;
int gcd(int a,int b)
{
 if (!(a%b)) return b;
  else return gcd(b,a%b);
}
int main()
{
  int i,j;
  scanf("%d",&n);
  for (i=1;i<=n;++i)
   {
     char c;
     scanf("%d%c%d",&fz[i],&c,&fm[i]);
   }
  lcm=fm[1];
  for (i=2;i<=n;++i) lcm=lcm*fm[i]/gcd(lcm,fm[i]);
  for (i=1;i<=n;++i)
   {
    int sm=fz[i]*(lcm/fm[i]);
    sum+=sm;
   }
  if (!(sum%lcm)) {printf("%d\n",sum/lcm); return 0;}
  int ans=gcd(lcm,sum);
  sum/=ans; lcm/=ans;
  printf("%d/%d",sum,lcm);
  return 0;
}

08:人民币支付

#include<cstdio>
using namespace std;
int main()
{
	int n;
	scanf("%d",&n);
	printf("%d\n",n/100);
	n%=100;
	printf("%d\n",n/50);
	n%=50;
	printf("%d\n",n/20);
	n%=20;
	printf("%d\n",n/10);
	n%=10;
	printf("%d\n",n/5);
	n%=5;
	printf("%d\n",n);
	return 0;
}

09:年龄与疾病

#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
int age[110];
int n,num[5];
int main()
{
	scanf("%d",&n);
	for(int i=1;i<=n;++i) 
	 {
	 	int x;
	 	scanf("%d",&x);
	 	if(x>=1&&x<=18) num[1]++;
	 	if(x>=19&&x<=35) num[2]++;
	 	if(x>35&&x<=60) num[3]++;
	 	if(x>60) num[4]++;
	 }
    printf("1-18: %.2lf%%\n",(double)num[1]/(double)n*(100.0));
    printf("19-35: %.2lf%%\n",(double)num[2]/(double)n*(100.0));
    printf("36-60: %.2lf%%\n",(double)num[3]/(double)n*(100.0));
    printf("60-: %.2lf%%\n",(double)num[4]/(double)n*(100.0));
    return 0;
}

10:求特殊自然数

#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
int a[5],b[5],opt;
inline bool check()
{
	for(int i=1;i<=3;++i)
	 if(a[i]!=b[i]) return 0;
	return 1;
}
int main()
{
	int i;
	scanf("%d",&opt);
	for(i=81;i<=342;++i)
	 {
	    int x=i,y=i;
	    a[1]=x%9; x/=9;
	    a[2]=x%9; x/=9;
	    a[3]=x%9; x/=9;
	    b[3]=y%7; y/=7;
	    b[2]=y%7; y/=7;
	    b[1]=y%7; y/=7;
	    if(check()) break;
	 }
	if(opt==1) printf("%d\n",i);
	if(opt==2) printf("%d%d%d\n",b[1],b[2],b[3]);
	if(opt==3) printf("%d%d%d\n",a[3],a[2],a[1]);
	return 0;
}