2018年南海区小学生程序设计竞赛详细答案

向右看齐 2022-01-28 07:01 279阅读 0赞

# 1 魔术卡片 #

AC代码

#include <iostream>
    #include <cstdio>
    using namespace std;
    
    int main()
    {
        freopen("hide.in", "r", stdin);
        freopen("hide.out", "w", stdout);
        
        int a1, b1, a2, b2;
        cin >> a1 >> b1 >> a2 >> b2;
        
        if (a1 < b1)
        {
            swap(a1, b1);
        }
        
        if (a2 < b2)
        {
            swap(a2, b2);
        }
        
        if((a1 >= a2 && b1 >= b2) || (a1 <= a2 && b1 <= b2))
        {
            cout << 1;
        }
        else
        {
        	cout << 2;
    	}
    	
        return 0;
    }

# 2 均分计算 #

AC代码

#include <iostream>
    #include <algorithm>
    #include <cstdio>
    using namespace std;
    
    int main(int argc, const char * argv[])
    {
        freopen("average.in", "r", stdin);
        freopen("average.out", "w", stdout);
    
        int n;
        cin >> n;
        int a[n];
        double score, sum = 0;
        for (int i = 0; i < n; i++)
        {
            cin >> a[i];
            sum += a[i];
        }
    
        sort(a, a + n);
    
        sum -= (a[0] + a[n - 1]);
    
        score = sum / (n - 2);
    
        printf("%.2f", score);
    
        return 0;
    }

# 3 出发能量 #

AC代码

#include<cstdio>
    
    int main()
    {
    	freopen("start.in", "r", stdin);
    	freopen("start.out", "w", stdout);
    	
    	int n;
    	scanf("%d", &n);
    	
    	int sum = 0;
    	int ans = 0;
    	for(int i = 0; i < n; i++)
    	{
    		int x;
    		scanf("%d", &x);
    		sum += x;
    		if(sum < 0)
    		{
    			ans += (-1 * sum);
    			sum = 0;
    		}
    	}
    	
    	printf("%d", ans);
    	
    	return 0;
    }

# 4 衰减 #

AC代码

#include<bits/stdc++.h>
    using namespace std;
    
    int n, ans[10], ansN, tot;
    
    void dfs(int num)
    {
        if(1 == num)
        {
            tot++;
            printf("%d-", n);
    
            for(int i=1; i<ansN; i++)
            {
                printf("%d-", ans[i]);
            }
            printf("%d\n", ans[ansN]);
    
            return;
        }
    
        num >>= 1;
        for(int i=1; i<=num; i++)
        {
            ans[++ansN] = i;
            dfs(i);
            --ansN;
        }
    }
    
    int main()
    {
        freopen("down.in","r",stdin);
        freopen("down.out","w",stdout);
    
        scanf("%d", &n);
        dfs(n);
        printf("%d", tot);
    
        return 0;
    }

# 5 拆除桥墩 #

AC代码

#include<bits/stdc++.h>
    using namespace std;
    
    const int MAXINF=0x7fffffff;
    const int MININF=0x80000000;
    
    int n,m,l,d[50002];
    
    bool check(int dmin)
    {
        int s=0, tot=0;
        for(int i=1; i<=n; i++)
        {
            s += d[i];
            if(s < dmin)
            {
                tot++;
            }
            else
            {
                s = 0;
            }
        }
    
        return (tot <= m);
    }
    
    int main()
    {
        freopen("remove.in", "r", stdin);
        freopen("remove.out", "w", stdout);
        cin >> l >> n >> m;
        for(int i=1; i<=n; i++)
        {
            cin >> d[i];
        }
    
        d[n+1] = l-d[n];
        for(int i=n; i>=2; i--)
        {
            d[i] = d[i] - d[i-1];
        }
    
        n++;
    
        int left = MAXINF, right = 0;
        for(int i=1; i<=n; i++)
        {
            left = min(left, d[i]);
            right += d[i];
        }
    
        while(left + 1 < right)
        {
            int mid = (left + right) >> 1;
            if(check(mid))
            {
                left = mid;
            }
            else
            {
                right = mid;
            }
        }
    
        cout << left;
    
        return 0;
    }

# 6 卜克游戏 #

AC代码
    #include<bits/stdc++.h>
    using namespace std;
    
    int f[3002],P[3002],S[3002],n;
    
    int main()
    {
        freopen("poker.in","r",stdin);
        freopen("poker.out","w",stdout);
    
        cin>>n;
        for(int i=1;i<=n;i++)
        {
            cin>>P[i];
        }
    
        for(int i=1;i<=n;i++)
        {
            cin>>S[i];
            S[i]+=S[i-1];
        }
    
        for(int i=1;i<=n;i++)
        {
            f[i]=f[i-1];
            for(int j=i-1;j>=1;j--)
            {
                if(P[i]==P[j])
                {
                    f[i]=max(f[i],S[i]-S[j-1]+f[j-1]);
                }
            }
        }
    
        cout<<f[n];
    
        return 0;
    }

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