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;
}