【codeforces 509A】Maximum in Table

【题目链接】:http://codeforces.com/contest/509/problem/A

【题意】

给你一个递推式f[i][j] = f[i-1][j]+f[i][j-1];
让你求f[i][j]的最大值;

【题解】

傻逼题

【Number Of WA】

0

【完整代码】

#include <bits/stdc++.h>
using namespace std;
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
#define LL long long
#define rep1(i,a,b) for (int i = a;i <= b;i++)
#define rep2(i,a,b) for (int i = a;i >= b;i--)
#define mp make_pair
#define ps push_back
#define fi first
#define se second
#define rei(x) cin >> x
#define pri(x) cout << x
#define ms(x,y) memset(x,y,sizeof x)

typedef pair<int,int> pii;
typedef pair<LL,LL> pll;

const int dx[9] = {0,1,-1,0,0,-1,-1,1,1};
const int dy[9] = {0,0,0,-1,1,-1,1,-1,1};
const double pi = acos(-1.0);
const int N = 20;

LL a[N][N],ans;
int n;

int main()
{
    //freopen("F:\\rush.txt","r",stdin);
    ios::sync_with_stdio(false);
    rei(n);
    rep1(i,1,n)
        a[i][1]=a[1][i]=1;
    rep1(i,2,n)
        rep1(j,2,n)
            a[i][j] = a[i-1][j]+a[i][j-1];
    ans = 1;
    rep1(i,1,n)
        rep1(j,1,n)
            ans = max(ans,a[i][j]);
    pri(ans<<endl);
    //printf("\n%.2lf sec \n", (double)clock() / CLOCKS_PER_SEC);
    return 0;
}