这次套路深啊,怎么还有改错题!。
上来看题,每个题目的输入数据都很大,果断上scanf,printf, 千万不能用cin,cout
1. 右上角的点,我的思路是先对每一行去重(题目好像说没有重的点耶!),每一行只有最右边的点才是候选点,然后对这些候选点按照y坐标,从大到小访问,要求相应的x是严格递增的,最后打印输出。
1 #include<bits/stdc++.h> 2 #define pb push_back 3 typedef long long ll; 4 using namespace std; 5 typedef pair<int, int> pii; 6 const int maxn = 1e3 + 10; 7 int n; 8 void solve() { 9 map<int, int> ma; 10 scanf("%d", &n); 11 int x, y; 12 for (int i = 0; i < n; i++) { 13 scanf("%d%d", &x, &y); 14 if(ma.count(y)) { 15 ma[y] = max(ma[y], x); 16 } else ma[y] = x; 17 } 18 vector<pii> res; 19 auto it = ma.rbegin(); 20 x = it->second - 1; 21 //cout << it->first <<endl; 22 while(it != ma.rend()) { 23 if(it->second > x) { 24 res.pb({it->second, it->first}); 25 x = it->second; 26 } 27 it++; 28 } 29 for (pii t : res) { 30 printf("%d %d\n", t.first, t.second); 31 } 32 } 33 34 int main() { 35 freopen("test.in", "r", stdin); 36 //freopen("test.out", "w", stdout); 37 solve(); 38 return 0; 39 }
2. 我认为是分治, 首先考虑数组的最小值,哪些区间可以取到取小值,取到最小值,使得结果最大,当然是和最大,那就是全部的数,接下来这个最小值就可以不考虑了,分别对左半和右半重复上面处理。
#include<bits/stdc++.h> #define pb push_back typedef long long ll; using namespace std; typedef pair<int, int> pii; const int maxn = 5e5 + 10; int n; ll a[maxn]; ll s[maxn]; ll f(int x, int y) { return s[y] - s[x - 1]; } ll res = 0; void work(int x, int y) { if(x > y) return; if(x == y) { res = max(res, a[x] * a[x]); return; } int p = x; for (int i = x; i <= y; i++) { if(a[i] < a[p]) { p = i; } } res = max(res, a[p] * f(x, y)); work(x, p - 1); work(p + 1, y); } void solve() { scanf("%d", &n); for (int i = 1; i <= n; i++) { scanf("%lld", &a[i]); s[i] = s[i - 1] + a[i]; } work(1, n); printf("%lld\n", res); } int main() { freopen("test.in", "r", stdin); //freopen("test.out", "w", stdout); solve(); return 0; }
3. 题目描述的挺复杂,就是多个角度的优先队列,然后就试了试刚学习的函数类(仿函数,函数对象,函数指针),以及lambda表达式,写了一下。
最后过了80%, 我的是按时间模拟的,题目的范围是【1,3000】,我的for循环是1-3000,突然想到有些任务可能到3000的时候一直没有程序员空闲,所以for循环至少要到6000才行,这样才能ac吧。
感觉模拟到6000也不行。应该是任务队列判空为止才行。
1 #include<bits/stdc++.h> 2 #define pb push_back 3 typedef long long ll; 4 using namespace std; 5 typedef pair<int, int> pii; 6 const int maxn = 3e3 + 10; 7 struct node { 8 int id, p, s, pr, t; 9 }; 10 int n, m, p; 11 node a[maxn]; 12 //这里扩大范围 13 int f[maxn * 2]; 14 int res[maxn]; 15 class cmp { 16 public: 17 bool operator()(const node&x, const node&y) { 18 if(x.pr == y.pr) { 19 if(x.t == y.t) { 20 return x.s < y.s; 21 } else { 22 return x.t < y.t; 23 } 24 } else { 25 return x.pr > y.pr; 26 } 27 } 28 }; 29 set<node, cmp> data[maxn]; 30 void solve() { 31 int x, y, x1, y1; 32 scanf("%d%d%d", &n, &m, &p); 33 for (int i = 1; i <= p; i++) { 34 scanf("%d%d%d%d", &x, &y, &x1, &y1); 35 a[i] = {i, x, y, x1, y1}; 36 } 37 sort(a + 1, a + p + 1, [](const node&x, const node&y)->bool{return x.s < y.s;}); 38 int cur = 0; 39 f[1] = m; 40 set<int> se; 41 x = 1; 42 int cnt = 0; 43 //这里应该模拟到6000, 保证所有的任务都有机会执行,或者更大。 44 for (int i = 1; i <= 3000; i++) { 45 cur += f[i]; 46 while(x <= p) { 47 //cout << x << endl; 48 if(a[x].s == i) { 49 data[a[x].p ].insert(a[x]); 50 //cout << "asd " << a[x].id << endl; 51 x++; 52 cnt++; 53 } else break; 54 } 55 if(cur <= 0 || cnt == 0) continue; 56 int t = cur; 57 58 for (int j = 0; j < t; j++) { 59 int id = -1; 60 int ti = 0; 61 for (int k = 1; k <= n; k++) { 62 if(data[k].size() == 0) 63 continue; 64 else { 65 // cout << k << " asd " << (data[k].begin())->t << endl; 66 if(id == -1 || (data[k].begin())->t < ti) { 67 id = k; 68 ti = (data[k].begin())->t; 69 }} 70 } 71 //cout << id << " " << ti << endl; 72 cur--; 73 cnt--; 74 node nd = *data[id].begin(); 75 data[id].erase(data[id].begin()); 76 res[nd.id] = i + nd.t; 77 f[i + nd.t]++; 78 79 if(cnt <= 0 || cur <= 0) break; 80 } 81 82 } 83 for (int i = 1; i <= p; i++) 84 printf("%d\n", res[i]); 85 } 86 87 int main() { 88 freopen("test.in", "r", stdin); 89 //freopen("test.out", "w", stdout); 90 solve(); 91 return 0; 92 }
时间: 2024-10-12 23:48:11