集训队19、20级标程 或 题解

计蒜客 T1866
集训队题目链接

#include
using namespace std;
int biao[25],n,m;
void dfs(int a,int k)
{
	if(k==m)
	{
		for(int i=1;i<=n;++i)
		{
			if(biao[i])
			{
				printf("%3d",i);
			}
		}
		putchar('n');
	}
	else
	{
		for(int i=a;i<=n;++i)
		{
			if(!biao[i])
			{
				biao[i]=1;
				dfs(i,k+1);
				biao[i]=0;
			}
		}
	}
}

int main()
{
	cin>>n>>m;
	dfs(1,0);
    return 0;
}

计蒜客 T1248
集训队题目链接

#include
using namespace std;

int biao[25],n,m;
vector v;

void dfs(int a,int k)
{
	if(k==n)
	{
		printf("%d=",n);
		for(int i=0;i>n;
	dfs(1,0);
    return 0;
}

计蒜客 T1217
集训队题目链接

#include 
using namespace std;
const int N = 20;
int n, m, x, y, cnt;
int tx[8] = {-2, -1, 1, 2, 2, 1, -2, -1};
int ty[8] = {-1, -2, -2, -1, 1, 2, 1, 2};
bool st[N][N];

void dfs(int x, int y, int t)
{
	if (t == m * n)
	{
		cnt++;
		return;
	}
	st[x][y] = true;
	for (int i = 0; i < 8; i++)
	{
		int dx = x + tx[i], dy = y + ty[i];
		if (dx < 0 || dx >= n || dy < 0 || dy >= m || st[dx][dy]) continue;
		dfs(dx, dy, t + 1);
	}
	st[x][y] = false;
}

int main()
{
	int T;
	scanf("%d", &T);
	while (T--)
	{
		cnt = 0;
		scanf("%d%d%d%d", &n, &m, &x, &y);
		dfs(x, y, 1);
		printf("%dn", cnt);
	}
	return 0;
}

计蒜客 T1684
集训队题目链接

#include 

using namespace std;
const int N = 20;
int n;
int a[N][2], MIN = 1e9;

void dfs(int k, int x, int y)
{
	if (x && y && abs(x - y) < MIN) MIN = abs(x - y);
	if (k >= n) return ;
	for (int i = 0; i < 2; ++i)
	{
		if (i) dfs(k + 1, x * a[k][0], y + a[k][1]);
		else dfs(k + 1, x, y);	
	}
}

int main()
{
	cin >> n;
	for (int i = 0; i < n; ++i) cin >> a[i][0] >> a[i][1];
	dfs(0, 1, 0);
	cout << MIN << "n";
	return 0;
}

计蒜客 T1771
集训队题目链接

#include 

using namespace std;
int k, MIN = 1e9, st[20] = {-1};
string s;
void dfs(int i)
{
	if (i == k)
	{
		int sum = 0, idx = 1;
		int x = 0;
		for (int j = 0; j < s.length(); ++j)
		{
			if (j == st[idx])
			{
				++idx;
				sum += x;
				x = 0;
			}
			x = x * 10 + s[j] - '0';
		}
		sum += x;
		if (sum < MIN) MIN = sum;
		return ;
	}
	for (int j = st[i - 1] + 1; j < s.length(); ++j)
	{
		st[i] = j;
		dfs(i+ 1);
	}
}
int main()
{
	cin >> s >> k;
	dfs(1);
	cout << MIN << "n";
	return 0;
}

计蒜客 T1211
集训队题目链接

#include 

using namespace std;

const int N = 55;
char s[N][N];
int w, h, st[N][N], cnt;
int dx[4] = {1, -1, 0, 0}, dy[4] = {0, 0, 1, -1};

void dfs(int x, int y)
{
	++cnt;
	for (int i = 0; i < 4; ++i)
	{
		int xx = x + dx[i];
		int yy = y + dy[i];
		if (xx >= 0 && xx < w && yy >= 0 && yy < h && !st[xx][yy] && s[xx][yy] == '.')
		{
			st[xx][yy] = 1;
			dfs(xx, yy);
		}
	}
}

int main()
{
	int x, y;
	cin >> h >> w;
	for (int i = 0; i < w; ++i)
	{
		for (int j = 0; j < h; ++j)
		{
			scanf(" %c", &s[i][j]);
			if (s[i][j] == '@')
			{
				x = i;
				y = j;
			}
		}
	}
	dfs(x, y);
	cout << cnt << "n";
	return 0;
}