Max Sum
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 198961 Accepted Submission(s): 46506
Problem Description
Given a sequence a[1],a[2],a[3]......a[n], 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
最大字段和 状态转移方程:if(dp[i-1]>=0) dp[i]=dp[i-1]+a[i] else dp[i]=a[i];
#include<cstdio> #include<cstring> #include<algorithm> #include<vector> using namespace std; const int MAXN=100005; int dp[MAXN]; int a[MAXN]; int n; int main() { int T; scanf("%d",&T); for(int cas=1;cas<=T;cas++) { scanf("%d",&n); for(int i=0;i<n;i++) scanf("%d",&a[i]); int maxn=dp[0]=a[0]; int l=0,r=0,ll=0,rr=0; for(int i=1;i<n;i++) { if(dp[i-1]>=0) { dp[i]=dp[i-1]+a[i]; r++; } else { l=r=i; dp[i]=a[i]; } if(dp[i]>maxn) { maxn=dp[i]; ll=l; rr=r; } } printf("Case %d: ",cas); printf("%d %d %d ",maxn,ll+1,rr+1); if(cas!=T) printf(" "); } return 0; }