1044. Shopping in Mars 解析

直接暴力弄会有两个case超时。

需要优化一下。

参考这个大神的思路的 http://blog.csdn.net/tiantangrenjian/article/details/19251273

#include <iostream>#include <vector>#include <climits>using namespace std;struct node {int i;int j;int sum;};vector <node> leq;vector <node> lov;int N, M;vector <int> link;vector <int> n2o;int main() {cin >> N >> M;int temp;node tempN;for (int i = 0; i < N; i++) {scanf("%d", &temp);link.push_back(temp);}int sum = 0;n2o.push_back(sum);for (int i = 0; i < N; i++) {sum += link[i];n2o.push_back(sum);}int min = INT_MAX;for (int i = 0; i < N; i++) {int left = i;int right = N;while (left < right) {int mid = (right + left) / 2;if (n2o[mid] - n2o[i] >= M) {right = mid;}elseleft = mid + 1;}tempN.j = right;tempN.i = i;tempN.sum = n2o[tempN.j] - n2o[tempN.i];tempN.i++;if (tempN.sum == M) {leq.push_back(tempN);}else if(tempN.sum > M) {if (tempN.sum < min) {lov.clear();lov.push_back(tempN);min = tempN.sum;}else if(tempN.sum == min){lov.push_back(tempN);}}}if (leq.size() != 0) {for (int i = 0; i < leq.size(); i++) {printf("%d-%d\n", leq[i].i , leq[i].j );}}else {for (int i = 0; i < lov.size(); i++) {printf("%d-%d\n", lov[i].i , lov[i].j );}}system("pause");return 0;}