周赛代码

A

#include<bits/stdc++.h>
using namespace std;
int a[1010],b[1010];
bool cmp1(int a,int b)
{
    return a<b;
}
bool cmp2(int a,int b)
{
    return a>b;
}
int main()
{
    int t,n,x;
    cin>>t;
    while(t--)
    {
        cin>>n>>x;
        for(int i=1;i<=n;i++){
                cin>>a[i];
        }
        for(int i=1;i<=n;i++){
                cin>>b[i];
        }
        sort(a+1,a+n+1,cmp1);
        sort(b+1,b+1+n,cmp2);
        int f;
        for(int i=1;i<=n;i++)
        {
            if(a[i]+b[i]>x){
                f=1;
                cout<<"NO"<<endl;
                break;
            }
            else f=0;
        }
        if(f==0) cout<<"YES"<<endl;
    }
    return 0;
}

B

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int t;
    cin>>t;
    while (t--)
    {
        int n;
        cin >> n;
        for (int i = 2 * n; i < 4 * n; i += 2)
            cout << i << " ";
        cout << endl;
    }
    return 0;
}

C

#include <bits/stdc++.h>
using namespace std;
int main()
{
    int t;
    cin>>t;
    while(t--)
    {
        int a,b,c,d;
        cin>>a>>b>>c>>d;
        cout<<max(a+b,c+d)<<endl;
    }
    return 0;
}

D

#include<bits/stdc++.h>
using namespace std;
int gcd(int a,int b){
    return b?gcd(b,a%b):a;
}
int main() {
    int a,b;
    while(cin>>a>>b){
        cout<<a*b/gcd(a,b)<<endl;
    }
    return 0;
}

E

二分解法

#include<bits/stdc++.h>
using namespace std;
#define ll long long

int n,a[200010],b[200010];

int check(int mid){
    ll tem=0;
    for(int i=1;i<=n;i++)
        if(a[i]>mid) tem+=b[i];//如果当前值大于中间值，那么就自己去取菜
    return tem<=mid;//判断当前区间是否可行
}

void solve(){
    cin>>n;
    int l=1,r=-1;
    for(int i=1;i<=n;i++) {
        cin>>a[i];
        r=max(a[i],r);//答案一定比最大值小或者等于最大值
    }
    for(int i=1;i<=n;i++) cin>>b[i];
    while(l<r){
        int mid=l+r>>1;
        if(check(mid)) r=mid;
        else l=mid+1;
    }
    cout<<l<<endl;
}

int main(){
    int t;  cin>>t;
    while(t--) solve();
    return 0;
}

前缀和解法

#include<bits/stdc++.h>
using namespace std;

struct node{
    int a,b;
}a[200010];
bool cmp(node a,node b){
    return a.a>b.a;
}
int main(){
    int t;
    cin>>t;
    while(t--){
        int n;
        cin>>n;
        for(int i=1;i<=n;i++) cin>>a[i].a;
        for(int i=1;i<=n;i++) cin>>a[i].b;
        int maxn=0,ti=0;//maxn为答案，ti为自取花费的总时间
        sort(a+1,a+1+n,cmp);//结构体排序
        for(int i=1;i<=n;i++) {
            if(a[i].a<=a[i].b)
                maxn=max(maxn,a[i].a);//更新答案
            else{
                if(ti+a[i].b<a[i].a){//若自取时间小于外卖时间，则自取
                    maxn=max(maxn,ti+a[i].b);
                    ti+=a[i].b;//更新当前自取花费的时间
                }
                else if(ti+a[i].b>=a[i].a){//否则外卖
                    maxn=max(maxn,a[i].a);
                }
            }
        }
        cout<<maxn<<endl;
    }
    return 0;
}

F

//这题代码不是我写的，找了个标程，不想写

#include <iostream>
#include <stdio.h>
#include <string.h>
#include <queue>
#include <algorithm>
using namespace std;
 
char map[35][35][35];
int vis[35][35][35];
int k,n,m,sx,sy,sz,ex,ey,ez;
int to[6][3] = {{0,0,1},{0,0,-1},{0,1,0},{0,-1,0},{1,0,0},{-1,0,0}};
 
struct node
{
    int x,y,z,step;
};
 
int check(int x,int y,int z)
{
    if(x<0 || y<0 || z<0 || x>=k || y>=n || z>=m)
        return 1;
    else if(map[x][y][z] == '#')
        return 1;
    else if(vis[x][y][z])
        return 1;
    return 0;
}
 
int bfs()
{
    int i;
    node a,next;
    queue<node> Q;
    a.x = sx,a.y = sy,a.z = sz;
    a.step = 0;
    vis[sx][sy][sz] = 1;
    Q.push(a);
    while(!Q.empty())
    {
        a = Q.front();
        Q.pop();
        if(a.x == ex && a.y == ey && a.z == ez)
            return a.step;
        for(i = 0; i<6; i++)
        {
            next = a;
            next.x = a.x+to[i][0];
            next.y = a.y+to[i][1];
            next.z = a.z+to[i][2];
            if(check(next.x,next.y,next.z))
                continue;
            vis[next.x][next.y][next.z] = 1;
            next.step = a.step+1;
            Q.push(next);
        }
    }
    return 0;
}
 
int main()
{
    int i,j,r;
    while(scanf("%d%d%d",&k,&n,&m),n+m+k)
    {
        for(i = 0; i<k; i++)
        {
            for(j = 0; j<n; j++)
            {
                scanf("%s",map[i][j]);
                for(r = 0; r<m; r++)
                {
                    if(map[i][j][r] == 'S')
                    {
                        sx = i,sy = j,sz = r;
                    }
                    else if(map[i][j][r] == 'E')
                    {
                        ex = i,ey = j,ez = r;
                    }
                }
            }
        }
        memset(vis,0,sizeof(vis));
        int ans;
        ans = bfs();
        if(ans)
            printf("Escaped in %d minute(s).\n",ans);
        else
            printf("Trapped!\n");
    }
 
    return 0;
}

G

#include<bits/stdc++.h>
using namespace std;

int main()
{
	int t,n;
	string s;
	cin >> t;
	while(t--)
	{
		cin >> n >> s;
		int sum1 = 0;
		int sum2 = 0;
		for(int i = 1 ; i < s.length(); i++)
		{
			if(s[i]=='1'&&s[i+1]=='1')
				sum1++;
			if(s[i]=='0'&&s[i+1]=='0')
				sum2++;
		}
		cout << max(sum1,sum2) << endl;
	}
	return 0;
}