numtri.cpp

USACO chapter one.May hope it useful to someone

/*
ID: chenkai4
PROG: numtri
LANG: C++
*/
#include <iostream>
#include <fstream>
using namespace std;
ifstream in("numtri.in");
ofstream out("numtri.out");

int R;
int f[1002][1002]={0};
int num[1002][1002];
#define Max(A,B) (A>B?A:B)
int main()
{
	in>>R;
	for(int a=1;a<=R;a++)
		for(int b=1;b<=a;b++)
			in>>num[a][b];
	for(int a=R;a>=1;a--)
		for(int b=1;b<=a;b++)
			f[a][b]=Max(f[a+1][b],f[a+1][b+1])+num[a][b];
	out<<f[1][1]<<endl;
	return 0;
}