hw for dfs

Author: AnfangRobkit

4.算法基础/week4/动态规划.md

@@ -333,6 +333,62 @@ Michael喜欢滑雪百这并不奇怪， 因为滑雪的确很刺激。可是为
 
 25
 
+```cpp
+#include<stdio.h>
+#include<iostream>
+#include<algorithm>
+#include<cstring>
+using namespace std;
+
+#define Max 100
+int map[Max][Max], length[Max][Max];
+int n=0, m=0;
+int max_length=0;
+int search(int a, int b);
+
+int main() 
+{
+    while(cin>>n>>m)
+    {
+        max_length = 0;
+        for(int i=0;i<n;i++)
+            for(int j=0; j<m; j++)
+                cin>>map[i][j];
+        memset(length, 0, sizeof(length));
+        for(int i=0; i<n; i++)
+            for(int j=0; j<m; j++)
+                search(i,j);
+        cout<<max_length<<endl;
+    }
+    return 0;
+}
+
+int search(int a, int b)
+{
+    if(length[a][b]!=0)
+        return length[a][b];
+    int max=0;
+    if(a-1>=0 && map[a][b]> map[a-1][b])
+    {
+        if(max<search(a-1,b))
+            max=search(a-1,b);
+    }
+    if(b-1>=0 && map[a][b-1] < map[a][b])
+        if(max < search(a,b-1))
+            max = search(a, b-1);
+    if(b+1<m && map[a][b+1]< map[a][b])
+        if(max < search(a, b+1))
+            max = search(a, b+1);
+    if(a+1<n && map[a][b] > map[a+1][b])
+        if(max < search(a+1,b)) 
+            max = search(a+1,b);
+    length[a][b] = max + 1;
+    if(max_length<length[a][b])
+        max_length = length[a][b];
+    return length[a][b];
+}
+```
+
 
 
 

4.算法基础/week5/DynamicProgramming_2.md

@@ -0,0 +1,79 @@
+#include <iostream>
+#include <math.h>
+using namespace std;
+#define LL long long
+#define MAX 310
+
+int T, N;
+int MIN;
+int flag;
+int number[10], son[10], ans[10], ans_num;
+
+void Dfs(int bit, int sum, int num)
+{ //bit表示当前还剩余的位数，sum当前的累积和,num是当前的深度
+    if (sum > T)
+        return; //无法裁剪，直接返回
+    if (bit == 0)
+    { //bit为0，说明裁剪完成，开始判定是否是最优解
+        if (T - sum == MIN)
+        {
+            flag = -1;
+            return; //有多个最优解，打印异常
+        }
+        if (T - sum > MIN)
+            return; //不是最优解，剪枝返回
+        for (int i = 0; i < num; i++)
+            ans[i] = son[i]; //相对最优解的存储，将裁剪的每一段纸的数据存储在相对优解中
+        MIN = T - sum;       //更新最优解
+        ans_num = num;       //更新最游记的深度，  即裁剪的纸的份数
+        flag = 1;            // flag = 1 表示存在一个解
+        return;              //结束这个搜索
+    }
+    int temp = 0;
+    for (; bit > 0; bit--)
+    {                                      //搜索核心，给出剩余纸张的位数，模拟剪裁
+        temp = temp * 10 + number[bit];    //用temp来模拟所有可能的裁剪方式
+        son[num] = temp;                   //son数组记录了当前裁剪方法中的每一段纸的值
+        Dfs(bit - 1, sum + temp, num + 1); //对剩余的知进行下一次搜索，纸张份数加1
+    }
+}
+int main()
+{
+    while (cin >> T >> N)
+    {
+        if (T == 0 && N == 0)
+            break;
+        if (T == N)
+        {
+            cout << T << " " << N << endl;
+            continue;
+        }
+        int num = 0;
+        MIN = 1 << 30;
+        flag = 0;
+        while (N)
+        {
+            number[++num] = N % 10;
+            N /= 10;
+        }
+        Dfs(num, 0, 0);
+        if (flag == 0)
+        {
+            cout << "error" << endl;
+        }
+        else
+        {
+            if (flag == -1)
+                cout << "rejected" << endl;
+            else
+            {
+                cout << T - MIN << " ";
+                for (int i = 0; i < ans_num - 1; i++)
+                    cout << ans[i] << " ";
+                cout << ans[ans_num - 1] << endl;
+            }
+        }
+    }
+    return 0;
+}
+//references: https://blog.csdn.net/iwts_24/article/details/79728793