@[lucy2012](/user/1252442)
```cpp
sort(a,a+n,cnt);
```
改为:
```cpp
sort(a+1,a+n+1,cnt);
```
by a_blue_cell @ 2024-03-16 16:23:37
@[lucy2012](/user/1252442) 不用特判 $sum=0$ ,题目中说 $sum>0$
by MrTerry @ 2024-03-16 18:36:37
@[lucy2012](/user/1252442) 冷知识:C++ 是有 bool 类型的
by clx201022 @ 2024-03-22 18:15:22
@[lucy2012](/user/1252442)
```cpp
#include<bits/stdc++.h>
using namespace std;
bool cnt(long long a,long long b){return a>b;}
long long a[20001],n,need,now=0;
int main()
{
cin>>n>>need;
for(int i=1;i<=n;i++)cin>>a[i];
sort(a+1,a+n+1,cnt);
for(int i=1;i<=n;i++)
{
if(now>=need)
{
cout<<i-1;
return 0;
}
now+=a[i];
}
if(now>=need)
{
cout<<n;
return 0;
}
return 0;
}
```
by clx201022 @ 2024-03-22 18:19:13
@[lucy2012](/user/1252442) 几个需要注意的点
1. for(...){...} () 中定义的变量可以在 {} 中使用
2. 数组定义从 0 开始
3. C++ 有 bool
by clx201022 @ 2024-03-22 18:23:09