$NOIP\ 2015\ Day1$ 模拟考试题解报告
\(NOIP\ 2015\ Day1\) 模拟考试题解报告
得分情况
\(T1\ 100\ Pts\)
\(T2\ 100\ Pts\)
\(T3\ 100\ Pts\)
总分: \(300\ Pts\)
考试过程
三道题都做过
十分钟过 \(T1\) 二十分钟过 \(T2\) 三十分钟过 \(T3\)
然后写对拍... 挨个模 \(T1\) 拍 \(T2\) ... 算 \(T3\) ... 等等... 到结束
题解
\(T1\) 神奇的幻方
模拟
代码
/*
Time: 6.20
Worker: Blank_space
Source:
*/
/*--------------------------------------------*/
#include<cstdio>
/*--------------------------------------头文件*/
inline void File() {
freopen("magic.in", "r", stdin);
freopen("magic.out", "w", stdout);
}
/*----------------------------------------文件*/
int n, x, y, mp[50][50];
/*------------------------------------变量定义*/
inline int read() {
int x = 0, f = 1; char ch = getchar();
while(ch < '0' || ch > '9') {if(ch == '-') f = -1; ch = getchar();}
while(ch >= '0' && ch <= '9') {x = (x << 3) + (x << 1) + (ch ^ 48); ch = getchar();}
return x * f;
}
/*----------------------------------------快读*/
/*----------------------------------------函数*/
int main() {
File();
n = read(); y = (n >> 1) + 1; x = 1; mp[x][y] = 1;
for(int i = 0; i <= n + 1; i++) mp[0][i] = mp[i][0] = mp[n + 1][i] = mp[i][n + 1] = 1;
for(int i = 2; i <= n * n; i++)
{
if(x == 1 && y != n) x = n, y++, mp[x][y] = i;
else if(x != 1 && y == n) y = 1, x--, mp[x][y] = i;
else if(x == 1 && y == n) x++, mp[x][y] = i;
else if(x != 1 && y != n)
if(!mp[x - 1][y + 1]) x--, y++, mp[x][y] = i; else x++, mp[x][y] = i;
}
for(int i = 1; i <= n; i++) {for(int j = 1; j <= n; j++) printf("%d ", mp[i][j]); puts("");}
return 0;
}
\(T2\) 信息传递
拓扑跑一遍 没走到过的搜一遍 统计数量即可
代码
/*
Time: 6.20
Worker: Blank_space
Source:
*/
/*--------------------------------------------*/
#include<cstdio>
#include<cstring>
#include<queue>
#define Abs(x) ((x) < 0 ? -(x) : (x))
#define Max(x, y) ((x) > (y) ? (x) : (y))
#define Min(x, y) ((x) < (y) ? (x) : (y))
#define Swap(x, y) ((x) ^= (y) ^= (x) ^= (y))
/*--------------------------------------头文件*/
const int B = 2e5 + 7;
const int mod = 1e9 + 7;
const int INF = 0x3f3f3f3f;
/*------------------------------------常量定义*/
inline void File() {
freopen("message.in", "r", stdin);
freopen("message.out", "w", stdout);
}
/*----------------------------------------文件*/
int n, in[B], cnt, ans = INF;
struct edge {int v, nxt;} e[B];
int head[B], ecnt;
std::queue <int> q;
bool vis[B];
/*------------------------------------变量定义*/
inline int read() {
int x = 0, f = 1; char ch = getchar();
while(ch < '0' || ch > '9') {if(ch == '-') f = -1; ch = getchar();}
while(ch >= '0' && ch <= '9') {x = (x << 3) + (x << 1) + (ch ^ 48); ch = getchar();}
return x * f;
}
/*----------------------------------------快读*/
void add_edge(int u, int v) {e[++ecnt] = (edge){v, head[u]}; head[u] = ecnt;}
void dfs(int u) {
vis[u] = 1; cnt++;
for(int i = head[u]; i; i = e[i].nxt) if(!vis[e[i].v]) dfs(e[i].v);
}
/*----------------------------------------函数*/
int main() {
// File();
n = read();
for(int i = 1, x; i <= n; i++) x = read(), add_edge(i, x), in[x]++;
for(int i = 1; i <= n; i++) if(!in[i]) q.push(i);
while(!q.empty())
{
int u = q.front(); q.pop(); vis[u] = 1;
for(int i = head[u]; i; i = e[i].nxt)
{
int v = e[i].v; in[v]--;
if(!in[v]) q.push(v);
}
}
for(int i = 1; i <= n; i++) if(!vis[i]) dfs(i), ans = Min(ans, cnt), cnt = 0;
printf("%d", ans);
return 0;
}
/*
7
2 4 2 3 1 7 6
*/
\(T3\) 斗地主
搜索
代码
/*
Time: 6.20
Worker: Blank_space
Source:
*/
/*--------------------------------------------*/
#include<cstdio>
#define Min(x, y) ((x) < (y) ? (x) : (y))
/*--------------------------------------头文件*/
const int A = 1e4 + 7;
const int B = 1e5 + 7;
const int C = 1e6 + 7;
const int D = 1e7 + 7;
const int mod = 1e9 + 7;
const int INF = 0x3f3f3f3f;
/*------------------------------------常量定义*/
inline void File() {
freopen("landlords.in", "r", stdin);
freopen("landlords.out", "w", stdout);
}
/*----------------------------------------文件*/
int T, n, s[20], ans;
/*------------------------------------变量定义*/
inline int read() {
int x = 0, f = 1; char ch = getchar();
while(ch < '0' || ch > '9') {if(ch == '-') f = -1; ch = getchar();}
while(ch >= '0' && ch <= '9') {x = (x << 3) + (x << 1) + (ch ^ 48); ch = getchar();}
return x * f;
}
/*----------------------------------------快读*/
void f1(int l, int r, int k) {for(int i = l; i <= r; i++) s[i] += k;}
void dfs(int t) {
if(t >= ans) return ;
int z = 0;
for(int i = 3; i <= 14; i++)
{
if(s[i]) z++; else z = 0;
if(z >= 5) {f1(i - z + 1, i, -1); dfs(t + 1); f1(i - z + 1, i, 1);}
}
z = 0;
for(int i = 3; i <= 14; i++)
{
if(s[i] > 1) z++; else z = 0;
if(z >= 3) {f1(i - z + 1, i, -2); dfs(t + 1); f1(i - z + 1, i, 2);}
}
z = 0;
for(int i = 3; i <= 14; i++)
{
if(s[i] > 2) z++; else z = 0;
if(z >= 2) {f1(i - z + 1, i, -3); dfs(t + 1); f1(i - z + 1, i, 3);}
}
for(int i = 2; i <= 14; i++) if(s[i] >= 3)
{
s[i] -= 3;
for(int j = 2; j <= 15; j++) if(s[j]) {s[j]--; dfs(t + 1); s[j]++;}
for(int j = 2; j <= 14; j++) if(s[j] > 1) {s[j] -= 2; dfs(t + 1); s[j] += 2;}
s[i] += 3;
}
for(int i = 2; i <= 14; i++) if(s[i] >= 4)
{
s[i] -= 4;
for(int j = 2; j <= 15; j++) if(s[j])
{
s[j]--;
for(int k = 2; k <= 15; k++) if(s[k]) {s[k]--; dfs(t + 1); s[k]++;}
s[j]++;
}
for(int j = 2; j <= 14; j++) if(s[j] > 1)
{
s[j] -= 2;
for(int k = 2; k <= 14; k++) if(s[k] > 1) {s[k] -= 2; dfs(t + 1); s[k] += 2;}
s[j] += 2;
}
s[i] += 4;
}
for(int i = 2; i <= 15; i++) if(s[i]) t++;
ans = Min(ans, t);
}
void clear() {ans = INF; for(int i = 2; i <= 15; i++) s[i] = 0;}
void work() {//A 14 王 15
for(int i = 1; i <= n; i++)
{
int x = read(), y = read();
if(x == 1) s[14]++;
else if(!x) s[15]++;
else s[x]++;
}
dfs(0);
printf("%d\n", ans);
}
/*----------------------------------------函数*/
int main() {
File();
T = read(); n = read(); while(T--) clear(), work();
return 0;
}
