钠 GZY整理贪心

目录

• CF140C New Year Snowmen
• CF161B Discounts
• P1842 奶牛玩杂技

CF140C New Year Snowmen

#include <bits/stdc++.h>
using namespace std;
#define gc getchar()
#define rep(i , x, y) for(int i = x;i <= y;++ i)
#define sep(i , x, y) for(int i = x;i >= y;-- i)
#define PII pair<int,int>
#define mk make_pair
#define fi first
#define se second
const int maxN = 1e5 + 7;

inline int gi() {
	int x = 0,f = 1;char c = gc;
	while(c < '0' || c > '9') {if(c == '-')f = -1;c = gc;}
	while(c >= '0' && c <= '9') {x = x * 10 + c - '0';c = gc;}
	return x * f;
}

int cnt[maxN];
int a[maxN];
priority_queue<PII> q;
struct Ans {
	int x,y,z;
}b[maxN];
int n;

void Read() {
	n = gi();
	rep(i , 1, n) a[i] = gi();
	return;
}

void Pre() {
	sort(a + 1,a + n + 1);
	rep(i , 1, n) {
		int p = lower_bound(a + 1,a + n + 1,a[i]) - a;
		cnt[p] ++;
	}
	for(int i = 1;i <= n;++ i) {
		if(cnt[i]) q.push(mk(cnt[i] , i));
	}
}

void Solve() {
	int k = 0;
	while(q.size() >= 3) {
		int x = q.top().se;q.pop();
		int y = q.top().se;q.pop();
		int z = q.top().se;q.pop();
		b[++ k] = (Ans) {a[x] , a[y], a[z]};
		if(b[k].z > b[k].y) swap(b[k].z , b[k].y);
		if(b[k].y > b[k].x) swap(b[k].x , b[k].y);
		if(b[k].z > b[k].y) swap(b[k].z , b[k].y);
		cnt[x] --;if(cnt[x]) q.push(mk(cnt[x] , x));
		cnt[y] --;if(cnt[y]) q.push(mk(cnt[y] , y));
		cnt[z] --;if(cnt[z]) q.push(mk(cnt[z] , z));
		
	}
	printf("%d\n",k);
	rep(i , 1, k) {
		printf("%d %d %d\n",b[i].x,b[i].y,b[i].z);
	}
}

int main() {
	Read();
	Pre();
	Solve();
	return 0;
}

CF161B Discounts

#include <bits/stdc++.h>
using namespace std;
#define gc getchar()
#define rep(i , x, y) for(int i = x;i <= y;++ i)
#define sep(i , x, y) for(int i = x;i >= y;-- i)
#define PII pair<int,int>
#define fi first
#define se second
#define mk make_pair
#define dbug(x) cout << "DEbug: " << x << '\n';

inline int gi() {
	int x = 0 ,f = 1;char c = gc;
	while(c < '0' || c > '9') {if(c == '-')f = -1;c = gc;}
	while(c >= '0' && c <= '9') {x = x * 10 + c - '0';c = gc;}
	return x * f;
}

int n, k;
const int maxN = 1e3 + 7;

struct Node {
	int id, c;
}a[maxN];
int t[maxN];

bool cmp(Node a, Node b) {
	return a.c > b.c;
}

bool vis[maxN];
int ans[maxN];

void Solve() {
	double ans1 = 0;
	int n = gi(), k = gi();
	for(int i = 1;i <= n;++ i) {
		a[i].id = i;
		a[i].c = gi();
		ans1 += a[i].c;
		t[i] = gi();
	}
	sort(a + 1, a + n + 1,cmp);
	int num = 0;
	for(int i = 1;i <= n;++ i) {
		if(num < k - 1 && t[a[i].id] == 1) {
			vis[i] = true;
			ans[++ num] = a[i].id;
			ans1 -= 1.0 * a[i].c / 2;
		}
	}
	bool flag = false;
	int minn = 0x7fffffff;
	for(int i = 1;i <= n;++ i) {
		if(!vis[i]) {
			if(t[a[i].id]== 1) {
				flag = true;
				minn = min(minn ,a[i].c);
			}
		}
	}
	int tot = num;
	for(int i = 1;i <= n;++ i) {
		if(!vis[i]) {
			if(tot == k - 1) break;
			tot ++;
			ans[tot] = a[i].id;
			vis[i] = true;
		}
	}
	if(flag) ans1 -= 1.0 * minn / 2;
	cout << ans1 << '\n';
	for(int i = 1;i < k;++ i) {
		printf("1 %d\n",ans[i]);
	}
		int cnt = 0;
	for(int i = 1;i <= n;++ i) {
		if(!vis[i]) cnt ++;
	}
	printf("%d ",cnt);
	for(int i = 1;i <= n;++ i) {
		if(!vis[i]) {
			printf("%d ",a[i].id);
		}
	}
}

int main() {
	Solve();
	return 0;
}

P1842 奶牛玩杂技

#include <bits/stdc++.h>
using namespace std;
#define gc getchar()
#define rep(i , x, y) for(int i = x;i <= y;++ i)
#define sep(i , x, y) for(int i = x;i >= y;-- i)
#define int long long
const int inf = 0x7fffffff;

inline int gi() {
	int x = 0,f = 1;char c = gc;
	while(c < '0' || c > '9') {if(c == '-')f = -1;c = gc;}
	while(c >= '0' && c <= '9') {x = x * 10 + c - '0';c = gc;}
	return x * f;
}
const int maxN = 100000 + 7;

struct Node {
	int w, s;
}a[maxN];

bool cmp(Node a , Node b) {return  a.s + a.w > b.s + b.w;}

signed main() {
	int n = gi();
	rep(i , 1, n) {
		a[i].w = gi();
		a[i].s = gi();
	}
	sort(a + 1 , a + n + 1, cmp);
	int ans = -inf;
	int sum = 0;
	sep(i , n, 1) {
		ans = max(ans , sum - a[i].s);
		sum += a[i].w;
	}
	printf("%lld",ans);
	return 0;
}