usaco_numtri.cpp

usaco自己做的1到5章的代码

/*
ID:wangyuc2
PROG:numtri
LANG:C++
*/
#include <iostream>
#include <fstream>
using namespace std;

int maxa(int a,int b)
{
   if(a>b) return a;
   else return b; 
}

int main()
{
    ifstream fin ("numtri.in");
    ofstream fout ("numtri.out");
    int a[600002];
    int n,i,j,m,max;
    fin>>n;
    m=n;
    j=0;
    while(n>0)
    {
        for(i=0;i<m-n+1;i++)
        {
            fin>>a[j];
            j++;
        }
        n--;
    }
    n=m;
    max=--j;
    while(n>1)
    {
        //i=1;
        for(i=1;i<n;i++) a[max-(2*n-1)+i]+=maxa(a[max-n+i],a[max-n+i+1]);
        
        max-=n;
        n--;
    }
    fout<<a[0]<<endl;
 //   for(i=0;i<j;i++) cout<<a[i];
    
  //  system("PAUSE");
    return 0;
}