Codeforces #839A: Arya and Bran 题解

这题直接模拟就好了

将这天能得到的糖果加进计数器，如果当天多于8个就给八个，否则给光

n天后，看能否给出不少于k个的糖果

#include <cstdio>#include <iostream>#include <cstring>#include <string>#include <cmath>#include <algorithm>#include <cstdlib>#include <utility>#include <map>#include <stack>#include <set>#include <vector>#include <queue>#include <deque>#include <sstream>#define x first#define y second#define mp make_pair#define pb push_back#define LL long long#define Pair pair<int,int>#define LOWBIT(x) x & (-x)using namespace std;const int MOD=1e9+7;const int INF=0x7ffffff;const int magic=348;int n,k;int a[1048];int c1,c2,c3;bool cmp(int x,int y){    return x>y;}int main (){int i;scanf("%d%d",&n,&k);for (i=1;i<=k;i++) scanf("%d",&a[i]);sort(a+1,a+k+1,cmp);c1=n;c2=n*2;/*for (i=1;i<=k;i++)if (a[i]/4<=c1){c1-=a[i]/4;a[i]%=4;}else{a[i]-=c1*4;c1=0;break;}if (c1!=0){for (i=1;i<=k;i++){if (a[i]==3){c1--;a[i]=0;}if (c1==0) break;}if (c1!=0){for (i=1;i<=k;i++){if (a[i]==2){c2--;a[i]=0;}if (c2==0) break;}if (c2!=0){c2+=2*c1;for (i=1;i<=k;i++)if (a[i]>0) c2--;if (c2<0){printf("NO\n");}else{printf("YES\n");}return 0;}else{int cc1=c1;for (i=1;i<=k;i++)if (a[i]==2){c1--;a[i]=0;}if (c1<0){printf("NO\n");return 0;}for (i=1;i<=k;i++)if (a[i]>0) c1--;if (c1<0){printf("NO\n");return 0;}printf("YES\n");return 0;}}else{for (i=1;i<=k;i++)if (a[i]!=0){if (a[i]%2==0) c2-=(a[i]+1)/2; else c2-=a[i]/2;}if (c2<0){printf("NO\n");}else{printf("YES\n");}}}else{for (i=1;i<=k;i++)if (a[i]!=0){if (a[i]%2==0) c2-=(a[i]+1)/2; else c2-=a[i]/2;}if (c2<0){printf("NO\n");}else{printf("YES\n");}}*/for (i=1;i<=k;i++){while (a[i]>=4 && c1>0){c1--;a[i]-=4;}while (a[i]>=3 && c1>0){c1--;a[i]-=3;}while (a[i]>=2 && c2>0){c2--;a[i]-=2;}while (a[i]>=2 && c1>0){c1--;c3++;a[i]-=2;}while (a[i]>0 && c3>0){c3--;a[i]--;}while (a[i]>0 && c2>0){c2--;a[i]--;}while (a[i]>0 && c1>0){c1--;c2++;a[i]--;}if (a[i]>0){printf("NO\n");return 0;}}printf("YES\n");return 0;}