小木棍
数据好强啊，但是感觉我第二次写的应该是哪里出了问题？
27分代码（wa了好多点但是没有t）：
1 #include<iostream> 2 #include<cstdio> 3 #include<algorithm> 4 5 using namespace std; 6 7 int a[70],vis[70]; 8 int n,cnt = 0,tot = 0,maxl = 0; 9 10 bool check(int len,int nowl,int lastid){ 11 int flag = 1,fail = -1; 12 for(int i = lastid+1;i <= n;i++)if(!vis[i]&&a[i] != fail){ 13 flag = 0; 14 if(nowl + a[i] == len){ 15 vis[i] = 1; 16 if(check(len,0,0))return true; 17 vis[i] = 0; 18 return false; 19 } 20 else if(nowl + a[i] < len){ 21 vis[i] = 1; 22 if(check(len,nowl+a[i],i))return true; 23 vis[i] = 0; 24 fail = a[i]; 25 } 26 } 27 if(flag)return true; 28 else return false; 29 }; 30 31 int main(){ 32 cin >> n; 33 for(int i = 1;i <= n;i++){ 34 cin >> a[++cnt]; 35 if(a[cnt] > 50)cnt--; 36 else tot += a[cnt],maxl = max(maxl,a[cnt]); 37 } 38 n = cnt; 39 sort(a+1,a+n+1); 40 reverse(a+1,a+n+1); 41 for(int l = maxl;l <= tot;l++) 42 if(tot % l == 0&&check(l,0,0)){ 43 cout << l << '\n'; 44 return 0; 45 } 46 }
ac代码：
#include<iostream> #include<cstdio> #include<algorithm> using namespace std; int a[70],vis[70]; int n,cnt = 0,tot = 0,maxl = 0,len; bool check(int cnt,int nowl,int lastid){ if(cnt > tot/len)return true; int fail = -1; for(int i = lastid+1;i <= n;i++)if(!vis[i]&&a[i] != fail){ if(nowl + a[i] == len){ vis[i] = 1; if(check(cnt+1,0,0))return true; vis[i] = 0; return false; } if(nowl + a[i] < len){ vis[i] = 1; if(check(cnt,nowl+a[i],i))return true; vis[i] = 0; fail = a[i]; if(nowl == 0||nowl+a[i] == len)return false; } } return false; }; int main(){ cin >> n; for(int i = 1;i <= n;i++){ cin >> a[++cnt]; if(a[cnt] > 50)cnt--; else tot += a[cnt],maxl = max(maxl,a[cnt]); } n = cnt; sort(a+1,a+n+1); reverse(a+1,a+n+1); for(len = maxl;len <= tot;len++) if(tot % len == 0&&check(1,0,0)){ cout << len << '\n'; return 0; } }
