题目链接:http://codeforces.com/contest/1150
第一题(模拟)
#include<bits/stdc++.h>
using namespace std;
#define debug puts("YES");
#define rep(x,y,z) for(int (x)=(y);(x)<(z);(x)++)
#define ll long long
#define lrt int l,int r,int rt
#define lson l,mid,rt<<1
#define rson mid+1,r,rt<<1|1
#define root l,r,rt
#define mst(a,b) memset((a),(b),sizeof(a))
#define pii pair<int,int>
#define fi first
#define se second
#define mk(x,y) make_pair(x,y)
const int mod=1e9+7;
const int maxn=3e5+100;
const int ub=1e6;
ll powmod(ll x,ll y){ll t; for(t=1;y;y>>=1,x=x*x%mod) if(y&1) t=t*x%mod; return t;}
ll gcd(ll x,ll y){
if(y==0) return x;
return gcd(y,x%y);
}
int n,m,r;
int mv1=1e9,mv2=-1;
int main(){
cin>>n>>m>>r;
rep(i,0,n){
int x;
cin>>x;
mv1=min(x,mv1);
}
rep(i,0,m){
int x;
cin>>x;
mv2=max(mv2,x);
}
cout<<max(r,(r%mv1)+(r/mv1*mv2))<<"\n";
return 0;
}
第二题(模拟)
#include<bits/stdc++.h>
using namespace std;
#define debug puts("YES");
#define rep(x,y,z) for(int (x)=(y);(x)<(z);(x)++)
#define ll long long
#define lrt int l,int r,int rt
#define lson l,mid,rt<<1
#define rson mid+1,r,rt<<1|1
#define root l,r,rt
#define mst(a,b) memset((a),(b),sizeof(a))
#define pii pair<int,int>
#define fi first
#define se second
#define mk(x,y) make_pair(x,y)
const int mod=1e9+7;
const int maxn=100;
const int ub=1e6;
ll powmod(ll x,ll y){ll t; for(t=1;y;y>>=1,x=x*x%mod) if(y&1) t=t*x%mod; return t;}
ll gcd(ll x,ll y){
if(y==0) return x;
return gcd(y,x%y);
}
int n,flag=1;
char s[maxn][maxn];
int judge(int x,int y){
if(x<0||x>=n) return 0;
if(y<0||y>=n) return 0;
if(s[x][y]=='#') return 0;
return 1;
}
int draw(int x,int y){
rep(i,0,3) if(judge(x+i,y)==0) return 0;
rep(i,0,3) if(judge(x+1,y-1+i)==0) return 0;
rep(i,0,3) s[x+i][y]=s[x+1][y-1+i]='#';
return 1;
}
int solve(){
rep(i,0,n) rep(j,0,n) if(s[i][j]!='#'){
if(draw(i,j)==0) {flag=0;return 0;}
}
return 1;
}
int main(){
scanf("%d",&n);
rep(i,0,n) scanf("%s",s[i]);
solve();
rep(i,0,n) rep(j,0,n) if(s[i][j]!='#') flag=0;
if(flag){
puts("YES");
}else{
puts("NO");
}
return 0;
}
第三题(贪心)
#include<bits/stdc++.h>
using namespace std;
#define debug puts("YES");
#define rep(x,y,z) for(int (x)=(y);(x)<(z);(x)++)
#define ll long long
#define lrt int l,int r,int rt
#define lson l,mid,rt<<1
#define rson mid+1,r,rt<<1|1
#define root l,r,rt
#define mst(a,b) memset((a),(b),sizeof(a))
#define pii pair<int,int>
#define fi first
#define se second
#define mk(x,y) make_pair(x,y)
const int mod=1e9+7;
const int maxn=3e5+100;
const int ub=1e6;
ll powmod(ll x,ll y){ll t; for(t=1;y;y>>=1,x=x*x%mod) if(y&1) t=t*x%mod; return t;}
ll gcd(ll x,ll y){
if(y==0) return x;
return gcd(y,x%y);
}
int n,x=0,y=0;
int judge(int x){
for(int i=2;i*i<=x;i++) if(x%i==0){
return 0;
}
return 1;
}
int main(){
cin>>n;
rep(i,0,n){
int v;cin>>v;
if(v==1) x++;
else y++;
}
if(x==0){
rep(i,0,y) cout<<"2 ";
}else if(y==0){
rep(i,0,x) cout<<"1 ";
}else{
x--,y--;
cout<<"2 1 ";
rep(i,0,y) cout<<"2 ";
rep(i,0,x) cout<<"1 ";
}
return 0;
}