pat 1007
output the one with the smallest indices i and j 我是真的蠢，我以为这句话叫我这种情况输出下标.....代码（=。按理说是可以优化内存的，不过我懒
1 #include <iostream> 2 #include <vector> 3 4 using namespace std; 5 const int inf = (1 << 31); 6 7 int main(void) 8 { 9 int n; 10 cin >> n; 11 vector<int> v;//存数据 12 vector<int> cnt;//对应位置的最大值 13 vector<int> index;//对应位置的最大值下标 14 v.reserve(n); 15 cnt.resize(n); 16 index.resize(n); 17 for (int i = 0;i < n;i++) 18 { 19 int tmp; 20 cin >> tmp; 21 v.push_back(tmp); 22 } 23 cnt[0] = v[0]; 24 index[0] = 0; 25 int max_sum = cnt[0]; 26 int max_i = 0; 27 bool unique = true; 28 for (int i = 1;i < n;i++) 29 { 30 cnt[i] = v[i]; 31 if (cnt[i - 1] >= 0) 32 { 33 cnt[i] += cnt[i - 1]; 34 index[i] = index[i - 1]; 35 } 36 else index[i] = i; 37 if (max_sum < cnt[i]) 38 { 39 max_sum = cnt[i]; 40 max_i = i; 41 } 42 } 43 if (max_sum < 0) 44 cout <<"0 " << v[0] << " " << v[v.size() - 1] << endl; 45 else 46 { 47 int flag = 0; 48 for (int i = 0;i < n;i++) 49 if (max_sum == cnt[i] && ++flag == 2) 50 unique = false; 51 cout << max_sum; 52 53 cout << " " << v[index[max_i]] << " " << v[max_i] << endl; 54 } 55 return 0; 56 }
好，来一波内存优化，参考：https://blog.csdn.net/liuchuo/article/details/52144554
这里，把t_left,i,cur看成一个当前行进的状态，并与left,right,max_s进行比较
1 #include <iostream> 2 #include <vector> 3 4 using namespace std; 5 const int inf = (1 << 31); 6 7 int main(void) 8 { 9 int n; 10 cin >> n; 11 vector<int> v(n); 12 int cur = 0; 13 //int temp; 14 int max_s = inf; 15 int left = 0, right = 0; 16 int t_left = 0; 17 for (int i = 0;i < n;i++) 18 { 19 cin >> v[i]; 20 cur += v[i]; 21 if (cur < 0) 22 { 23 cur = 0; 24 t_left = i + 1; 25 } 26 else if (cur > max_s) 27 { 28 left = t_left; 29 max_s = cur; 30 right = i; 31 } 32 } 33 if (max_s < 0)cout << "0 " << v[0] << " " << v[n - 1]; 34 else cout << max_s << " " << v[left] << " " << v[right]; 35 cout << endl; 36 37 return 0; 38 }
