练习时长两个月的菜基，求助大佬0s卡过

不多哔哔，直接上代码

#pragma GCC optimize("Ofast")
#pragma GCC optimize("inline")
#include<iostream>
#include<cstdio>
using namespace std;
#define max(A,B) (A>B?A:B)
#define re register short int
inline int read()
{
    register int x(0),f(0);register char ch(getchar());
    while(!isdigit(ch))f|=(ch=='-'),ch=getchar();
    while(isdigit(ch))x=(x<<1)+(x<<3)+(ch^48),ch=getchar();
    return x=f?-x:x;
}

const int MAXN=1005;

int n,f[MAXN],maxn;

int main()
{
    freopen("a.in","r",stdin);
    freopen("a.out","w",stdout);
    n=read();
    for(re i(1);i<=n;++i)
        for(re j(i);j>=1;--j)
            f[j]=read()+max(f[j-1],f[j]);
    for(re i(1);i<=n;++i)
        maxn=max(maxn,f[i]);
    printf("%d",maxn);
    return 0;
}