A题
/* ID: neverchanje PROG: LANG: C++11 */ #include<vector> #include<iostream> #include<cstring> #include<string> #include<algorithm> #include<cmath> #include<cstdio> #include<set> #include<queue> #include<map> using namespace std; #define INF 0Xfffffff #define maxn typedef long long ll; typedef pair<int,int> pii; typedef vector<int,int> vii; int p,n; bool h[301]; int a[301]; int main(){ // freopen("a.txt","r",stdin); // freopen(".out","w",stdout); while(cin>>p>>n){ int x;bool find=0; memset(h,0,sizeof(h)); for(int i=1;i<=n;i++) cin>>a[i]; for(int i=1;i<=n;i++){ if(h[a[i]%p]){ cout<<i<<endl; find=1; break; } else h[a[i]%p]=1; } if(!find)puts("-1"); } return 0; } /* DESCRIPTION: */
B题 贪心
/* ID: neverchanje PROG: LANG: C++11 */ #include<vector> #include<iostream> #include<cstring> #include<string> #include<algorithm> #include<cmath> #include<cstdio> #include<set> #include<queue> #include<map> using namespace std; #define INF 0Xfffffff #define maxn typedef long long ll; typedef pair<int,int> pii; typedef vector<int,int> vii; char s[1001]; int k; int h[27]; int main(){ // freopen("a.txt","r",stdin); // freopen(".out","w",stdout); while(cin>>s){ cin>>k; int m=-1; for(int i=0;i<26;i++){ cin>>h[i]; if(h[i]>m) m=h[i]; } ll ans=0;int l=strlen(s); for(int i=0;i<l;i++) ans+=h[s[i]-‘a‘]*(i+1); ans+=(l+1+l+k)*k*m/2; cout<<ans<<endl; } return 0; } /* DESCRIPTION: */
C题 dp
/* ID: neverchanje PROG: LANG: C++11 */ #include<vector> #include<iostream> #include<cstring> #include<string> #include<algorithm> #include<cmath> #include<cstdio> #include<set> #include<queue> #include<map> using namespace std; #define INF 0Xfffffff #define maxn 100001 typedef long long ll; typedef pair<int,int> pii; typedef vector<int,int> vii; int n,a[maxn],s[maxn],e[maxn]; int main(){ // freopen("a.txt","r",stdin); // freopen(".out","w",stdout); while(cin>>n){ for(int i=1;i<=n;i++) cin>>a[i]; s[n]=1; for(int i=n-1;i>=1;i--) s[i] = (a[i]<a[i+1])? s[i+1]+1 : 1; e[1]=1; for(int i=2;i<=n;i++) e[i] = (a[i]>a[i-1])? e[i-1]+1 : 1; int ans = max( e[n-1]+1 , s[2]+1 ); for(int i=2;i<=n-1;i++){ if(a[i+1] - a[i-1]>1) ans = max( ans , e[i-1]+s[i+1]+1 ); else ans = max(ans , max(s[i+1],e[i-1])+1 ); } cout<<ans<<endl; } return 0; } /* DESCRIPTION: 题还是做得太少,这题跟lis一点关系都没有 以i为开头的最长连续序列s[i],以i为结尾的最长连续序列e[i] 这题恶心,按理来说ai>0,但是数据允许你把ai改成0 */
D题 优先队列
/* ID: neverchanje PROG: LANG: C++11 */ #include<vector> #include<iostream> #include<cstring> #include<string> #include<algorithm> #include<cmath> #include<cstdio> #include<set> #include<queue> #include<map> using namespace std; #define INF 1e9 #define maxn #define rep(i,x,y) for(int i=x;i<=y;i++) #define mset(x) memset(x,0,sizeof(x)) typedef long long ll; typedef pair<int,int> pii; typedef vector<int,int> vii; int n,m,k,p; int row[1001],col[1001]; ll sc[1000000],sr[1000000]; int main(){ // freopen("a.txt","r",stdin); // freopen(".out","w",stdout); cin>>n>>m>>k>>p; mset(row);mset(col); int x; rep(i,0,n-1) rep(j,0,m-1){ cin>>x; row[i]+=x; col[j]+=x; } priority_queue<int> c,r; rep(i,0,m-1) c.push(col[i]); rep(i,0,n-1) r.push(row[i]); sc[0]=0;sr[0]=0; rep(i,1,k){//把最大的k列存进c中 int x=c.top() , y=r.top(); sc[i] = sc[i-1]+x; sr[i] = sr[i-1]+y; c.pop(); r.pop(); c.push(x-n*p); r.push(y-m*p); } ll ans = sr[k]; rep(i,1,k){ ans = max( ans, sc[i]+sr[k-i]-1ll*(k-i)*i*p ); } cout<<ans<<endl; return 0; } /* DESCRIPTION: 按照某种取法得到解,解与行列选择的顺序无关 取了i列,(k-i)行 ans = max( sigma(col) + sigma(row) - (k-i)*i*p ) 将col和row分别用priority_queue储存 枚举i,意味着要把最大的k个列存进prq中 由于i列中可能会有重复的 算法就是:先在prq中找最大col, 把col-n*p存进去,如此循环k次 这样prq里有了最大的k个数 不过这样占用的内存过大 要及时删除 由于最大会有1e12的数,故注意要用long long priority_queue.top()默认返回最大值 */
Codeforces Round #FF(255) (Div. 2),布布扣,bubuko.com
时间: 2024-10-16 03:19:22