PTA甲级

1006 Sign In and Sign Out

经典的排序算法

#include<iostream>
#include<algorithm>
#include<vector>using namespace std;int n;
struct node
{string id;int ti , to;
};
vector<node>v;
bool cmpin(node a , node b)
{return a.ti < b.ti;
}bool cmpde(node a , node b)
{return a.to > b.to;
}int main()
{cin >> n;while(n --){string id;char ch;int h1 , h2 , m1 , m2 , s1 , s2;cin >> id >> h1 >> ch >> m1 >> ch >> s1 >> h2 >> ch >> m2 >> ch >> s2;v.push_back({id , h1 * 3600 + m1 * 60 + s1 , h2 * 3600 + m2 * 60 + s2});}sort(v.begin() , v.end() , cmpin);cout << v[0].id << " ";sort(v.begin() , v.end() , cmpde);cout << v[0].id;return 0;
}

1007 Maximum Subsequence Sum

有点dp的样子

#include<iostream>using namespace std;const int N = 1e6 + 10;
typedef long long ll;
ll a[N];
ll sum = 0 , res = -1;
ll l = 0 , r = 0;
ll n;int main()
{cin >> n;ll t = 0;r = n - 1;for(int i = 0;i < n;i ++){cin >> a[i];sum += a[i];if(sum < 0){ //  重新计算sum = 0;t = i + 1;}else if(sum > res){res = sum;r = i;l = t;}}if(res < 0) res = 0;cout << res << " " << a[l] << " " << a[r] << endl;return 0;
}