HDU1003 Max Sum(DP)

Max Sum

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 228524    Accepted Submission(s): 53767

Problem Description
Given a sequence a[1],a[2],a[3]......a
, your job is to calculate the max sum of a sub-sequence. For example, given (6,-1,5,4,-7), the max sum in this sequence is 6 + (-1) + 5 + 4 = 14.

Input
The first line of the input contains an integer T(1<=T<=20) which means the number of test cases. Then T lines follow, each line starts with a number N(1<=N<=100000), then N integers followed(all the integers are between -1000 and 1000).

Output
For each test case, you should output two lines. The first line is "Case #:", # means the number of the test case. The second line contains three integers, the Max Sum in the sequence, the start position of the sub-sequence, the end position of the sub-sequence. If there are more than one result, output the first one. Output a blank line between two cases.

Sample Input
2
5 6 -1 5 4 -7
7 0 6 -1 1 -6 7 -5

Sample Output
Case 1:
14 1 4

Case 2:
7 1 6

12月12日唉,那时候电脑也是在这一天买的2333.
不能对不起自己的电脑，要让它发光发热。
求最大子段和，注意初始化(-1000~1000)，所以初始化的值不是0,要在-1000以下，设置为-1001就可以，注意一下格式。

#include<iostream>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<cctype>
#include<cmath>
#include<ctime>
#include<string>
#include<stack>
#include<deque>
#include<queue>
#include<list>
#include<set>
#include<map>
#include<cstdio>
#include<limits.h>
#define MOD 1000000007
#define fir first
#define sec second
#define fin freopen("/home/ostreambaba/文档/input.txt", "r", stdin)
#define fout freopen("/home/ostreambaba/文档/output.txt", "w", stdout)
#define mes(x, m) memset(x, m, sizeof(x))
#define Pii pair<int, int>
#define Pll pair<ll, ll>
#define INF 1e9+7
#define inf 0x3f3f3f3f

#define Pi 4.0*atan(1.0)
#define Sqrt(x) (x)*(x)

#define lowbit(x) (x&(-x))
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1

typedef long long ll;
typedef unsigned long long ull;
const double eps = 1e-12;
const int maxn = 1000000+10;
using namespace std;
inline int read(){
int x(0),f(1);
char ch=getchar();
while (ch<'0'||ch>'9') {if (ch=='-') f=-1;ch=getchar();}
while (ch>='0'&&ch<='9') x=x*10+ch-'0',ch=getchar();
return x*f;
}
int dp[maxn];
int main()
{
fin;
int t,n;
t=read();
for(int cnt=1;cnt<=t;++cnt){
int Max=-1001,cur=0;
n=read();
int st,ed,tmp;
st=ed=tmp=1;
for(int i=1;i<=n;++i){
dp[i]=read();
cur+=dp[i];
if(cur>Max){
Max=cur;
st=tmp;
ed=i;
}
if(cur<0){
cur=0;
tmp=i+1;
}
}
printf("Case %d:\n%d %d %d\n",cnt,Max,st,ed);
if(cnt!=t){
cout<<endl;
}
}
return 0;
}