subtask1第一个点被hack了求助

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N=1e6+5;
int n,MOD;
ll a[N],f[N],g[N],ans;
void solve1(){
	f[0]=LONG_LONG_MIN;
	for(int i=1;i<=n;++i)
		f[i]=max(f[i-1],0ll)+a[i];
	for(int i=1;i<=n;++i)
		f[i]=max(f[i-1],f[i]);
	for(int i=1;i<=n;++i)
		f[i]%=MOD;
}
void solve2(){
	ll now=f[1];
	bool flg=true;
	for(int i=2;i<=n;++i){
		if(f[i]>0)now+=f[i];
		if(now>0){
			flg=false;//特判最终答案是不是f[1] 
			break;
		}
	}
	if(flg)return void(printf("%lld\n",f[1]%MOD));
	g[1]=f[1];
	now=g[1]+f[1];
	for(int i=2;i<=n;++i)
		g[i]=now,now=max(now,g[i]+f[i]);
	printf("%lld\n",g[n]%MOD);
}
signed main(){
//	freopen("number.in","r",stdin);
//	freopen("number.out","w",stdout);
	scanf("%d%d",&n,&MOD);
	for(int i=1;i<=n;++i)
		scanf("%lld",&a[i]);
	solve1();//求最大连续和 
	solve2();//将特征值转换为分数
	return 0;
}