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
题意是要求最大连续和,与以往不同的是追加输出子串的头尾位置,这个可以用结构体记录,最坑的是没有注意到格式说每两个case间要空一行。
代码:
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#include <stdio.h> #include<string.h> #include<algorithm> using namespace std; int a[100005]; struct studen { long long sum; int l,r; }dp[100005]; long long maxw(long long x,long long y) { if(x>y) return x; else return y; } int main() { int n,i,m,s=0; scanf("%d",&m); while(m--) { s++; scanf("%d",&n); for(i=1;i<=n;i++) { scanf("%d",&a[i]); dp[i].sum=a[i];dp[i].l=i;dp[i].r=i; } studen max1=dp[1]; for(i=2;i<=n;i++) { dp[i].sum=maxw(a[i],dp[i-1].sum+a[i]); if(dp[i-1].sum>=0) dp[i].l=dp[i-1].l; else dp[i].l=i; dp[i].r=i; if(dp[i].sum>=max1.sum) { max1=dp[i]; } } printf("Case %d:\n",s); printf("%lld %d %d\n",max1.sum,max1.l,max1.r); if(m) printf("\n"); } return 0; }