hdu_5742_It's All In The Mind

题目链接：hdu_5742_It's All In The Mind

题意：

有一个部分的数列，让你找一个满足他给的三个条件的数列，使前两个数的和除这个数列的sum最大

题解：

xjb贪心一下就行了。

#include<cstdio>
#include<cmath>
#define F(i,a,b) for(int i=a;i<=b;i++)

int gcd(int a,int b){return b?gcd(b,a%b):a;}

int a[110],t,n,m,x,y;

int main()
{
    scanf("%d",&t);
    while(t--)
    {
        scanf("%d%d",&n,&m);
        F(i,1,n)a[i]=-1;
        F(i,1,m)scanf("%d%d",&x,&y),a[x]=y;
        int sum=0,pre=0,zi=0,gc;
        for(int i=n;i>2;i--)
        {
            if(a[i]==-1)a[i]=pre;
            else pre=a[i];
            sum+=a[i];
        }
        pre=100;
        F(i,1,2)if(a[i]==-1)sum+=pre,zi+=pre;
        else pre=a[i],sum+=a[i],zi+=a[i];
        gc=gcd(sum,zi),sum/=gc,zi/=gc;
        printf("%d/%d\n",zi,sum);
    }
}