Files
2023-08-03 09:22:52 +08:00

41 lines
849 B
C++

#include<cstdio>
#include<cstring>
#define min(a,b) ((a)<(b)?(a):(b))
#define max(a,b) ((a)>(b)?(a):(b))
#define INT_MAX 10000000
int i,t,n,ans,maxprice,minprice;
int a[100005],dp1[100005],dp2[100005];
void read(int &x)
{
int f=1;x=0;
char c=getchar();
for (;!(c>='0'&&c<='9');c=getchar()) if(c=='-') f=-1;
for (;c>='0'&&c<='9';c=getchar()) x=x*10+c-'0';
x*=f;
}
int main()
{
read(t);
while (t--)
{
memset(dp1,0,sizeof(dp1));
memset(dp2,0,sizeof(dp2));
ans=0; minprice=INT_MAX; read(n);
for (i=1;i<=n;i++) read(a[i]);
for (i=1;i<=n;i++)
{
minprice=min(minprice,a[i]);
dp1[i]=max(dp1[i-1],a[i]-minprice);
}
maxprice=-INT_MAX;
for (i=n;i>=1;i--)
{
maxprice=max(maxprice,a[i]);
dp2[i]=max(dp2[i+1],maxprice-a[i]);
}
for (i=1;i<=n;i++) ans=max(ans,dp1[i]+dp2[i+1]);
printf("%d\n",ans);
}
return 0;
}