http://bestcoder.hdu.edu.cn/contests/contest_show.php?cid=861
没想到6点就开始了，七点多才开始打，A了1001和1005后就挂机了。。
太菜了我
签到题。分子分母都趋近于无穷大，又都是多项式，用洛必达就好了，比较f和g的最高次数
1 #include<iostream> 2 #include<sstream> 3 #include<fstream> 4 #include<algorithm> 5 #include<cstring> 6 #include<iomanip> 7 #include<cstdlib> 8 #include<cctype> 9 #include<vector> 10 #include<string> 11 #include<cmath> 12 #include<ctime> 13 #include<stack> 14 #include<queue> 15 #include<map> 16 #include<set> 17 #define mem(a,b) memset(a,b,sizeof(a)) 18 #define random(a,b) (rand()%(b-a+1)+a) 19 #define ll long long 20 #define ull unsigned long long 21 #define e 2.71828182 22 #define Pi acos(-1.0) 23 #define ls(rt) (rt<<1) 24 #define rs(rt) (rt<<1|1) 25 #define lowbit(x) (x&(-x)) 26 using namespace std; 27 const int MAXN=1e3+5; 28 int f[MAXN],g[MAXN]; 29 int n; 30 void solve() 31 { 32 for(int i=n-1;i>=0;--i) 33 { 34 if(!f[i]&&!g[i]) continue; 35 if(f[i]&&g[i]) 36 { 37 int Gcd=__gcd(f[i],g[i]); 38 cout<<f[i]/Gcd<<'/'<<g[i]/Gcd<<" "; 39 return ; 40 } 41 else if(f[i]) 42 { 43 cout<<"1/0 "; 44 return; 45 } 46 else if(g[i]) 47 { 48 cout<<"0/1 "; 49 return; 50 } 51 } 52 } 53 int read() 54 { 55 int s=1,x=0; 56 char ch=getchar(); 57 while(!isdigit(ch)) {if(ch=='-') s=-1;ch=getchar();} 58 while(isdigit(ch)) {x=10*x+ch-'0';ch=getchar();} 59 return x*s; 60 } 61 int main() 62 { 63 int test=read(); 64 while(test--) 65 { 66 n=read(); 67 for(int i=0;i<n;++i) f[i]=read(); 68 for(int i=0;i<n;++i) g[i]=read(); 69 solve(); 70 } 71 return 0; 72 }
打表找规律。6个为一周期。下面是当时的草稿。
1 #include<iostream> 2 #include<sstream> 3 #include<fstream> 4 #include<algorithm> 5 #include<cstring> 6 #include<iomanip> 7 #include<cstdlib> 8 #include<cctype> 9 #include<vector> 10 #include<string> 11 #include<cmath> 12 #include<ctime> 13 #include<stack> 14 #include<queue> 15 #include<map> 16 #include<set> 17 #define mem(a,b) memset(a,b,sizeof(a)) 18 #define random(a,b) (rand()%(b-a+1)+a) 19 #define ll long long 20 #define ull unsigned long long 21 #define e 2.71828182 22 #define Pi acos(-1.0) 23 #define ls(rt) (rt<<1) 24 #define rs(rt) (rt<<1|1) 25 #define lowbit(x) (x&(-x)) 26 using namespace std; 27 const int MAXN=1e6+5; 28 int a[MAXN],sum[MAXN]; 29 ll read() 30 { 31 ll s=1,x=0; 32 char ch=getchar(); 33 while(!isdigit(ch)) {if(ch=='-') s=-1;ch=getchar();} 34 while(isdigit(ch)) {x=10*x+ch-'0';ch=getchar();} 35 return x*s; 36 } 37 int main() 38 { 39 // a[1]=1;sum[1]=1; 40 // for(int i=2;i<=100;++i) 41 // { 42 // a[i]=sum[i-1]%i; 43 // sum[i]=sum[i-1]+i*a[i]; 44 // } 45 // for(int i=1;i<=100;++i) 46 // cout<<"i: "<<i<<" a[i]: "<<a[i]<<endl; 47 int test=read(); 48 ll ans; 49 while(test--) 50 { 51 ll n=read(); 52 ll tmp=(n+1)>>1; 53 if(n%2==0) 54 { 55 if(n%6==4) 56 ans=tmp+tmp-1; 57 else ans=tmp; 58 } 59 else 60 { 61 if(n%6==1) 62 ans=tmp+n/6; 63 else ans=n/6; 64 } 65 cout<<ans<<" "; 66 } 67 return 0; 68 }
剩下的等题解再补