求调

#include <iostream>
using namespace std;
#define ing long long
int a[10000016];
signed main()
{
	int x,n,ans=0,q,i;
	cin>>n>>x;
	for (i=1;i<=n;i++)
	{
		cin>>a[i];
	}
	for (i=1;i<=n;i++)
	{
		if (a[i]+a[i-1]>x)
		{
			q=(a[i]+a[i-1])-x;
			ans=ans+q;
			a[i]=a[i]-a[i-1]+a[i]-x;
		}
	}
	cout<<ans;
	return 0;
}