2015 Multi-University Training Contest 2（hdu 5300 - hdu 5309）

1.Angry Trees

2.Buildings

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=5301

解题思路：http://blog.csdn.net/piaocoder/article/details/47657487

#include <iostream>  
#include <cstdio>  
#include <algorithm>  
using namespace std;  
  
int main(){  
    int n,m,x,y;  
    while(scanf("%d%d%d%d",&n,&m,&x,&y) != EOF){  
        if(n > m){  
            swap(n,m);  
            swap(x,y);  
        }   //n<=m  
        int ans = (n + 1) / 2,answer;  
        int left = y,right = m - y+1;  
        int up = x-1,down = n-x;  
        if(n % 2 && n == m && x == y && x == (n+1)/2)  
            answer = n / 2;  
        else if(x == ans || x == ans + 1 || y == 1 || y == m)  
            answer = ans;  
        else if(min(left, right) > ans)  
            answer= min(max(up,down),min(left,right));  
        else  
            answer = ans;  
        printf("%d\n",answer);  
    }  
    return 0;  
}

3.Connect the Graph

4.Delicious Apples

5.Eastest Magical Day Seep Group's Summer

6.Friends

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=5305

解题思路：/article/1958478.html

#include <iostream>  
#include <cstdio>  
#include <cstring>  
using namespace std;  
  
int n,m;  
int a[30],b[30],cnt;  
int sum[10],on[10],off[10];//sum记录每个点的度数，on记录每个点的online，off记录每个点的offline  
  
bool judge(){  
    for(int i = 1; i <= n; i++){  
        if(on[i] != off[i])  
            return false;  
    }  
    return true;  
}  
  
void dfs(int cur){  
    if(cur == m+1){  
        if(judge()){  
            cnt++;  
            return;  
        }  
    }  
    int x = a[cur], y = b[cur];  
    if(on[x] < sum[x]/2 && on[y] < sum[y]/2){  
        on[x]++;  
        on[y]++;  
        dfs(cur+1);  
        on[x]--;  
        on[y]--;  
    }  
    if(off[x] < sum[x]/2 && off[y] < sum[y]/2){  
        off[x]++;  
        off[y]++;  
        dfs(cur+1);  
        off[x]--;  
        off[y]--;  
    }  
}  
  
int main(){  
    int T;  
    scanf("%d",&T);  
    while(T--){  
        memset(on,0,sizeof(on));  
        memset(off,0,sizeof(off));  
        memset(sum,0,sizeof(sum));  
        int flag = 1;  
        cnt = 0;  
        scanf("%d%d",&n,&m);  
        for(int i = 1; i <= m; i++){  
            scanf("%d%d",&a[i],&b[i]);  
            sum[a[i]]++;  
            sum[b[i]]++;  
        }  
        for(int i = 1; i <= n; i++){  
            if(sum[i] % 2){  
                flag = 0;  
                break;  
            }  
        }  
        if(flag){  
            dfs(1);  
            printf("%d\n",cnt);  
        }  
        else  
            printf("0\n");  
    }  
    return 0;  
}

7.Gorgeous Sequence

8.He is Flying

9.I Wanna Become A 24-Point Master

题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=5308

解题思路：/article/1958480.html

#include <iostream>  
#include <cstdio>  
using namespace std;  
int main(){  
    int i,n;  
    while(~scanf("%d",&n)){  
        if(n <= 3)  
            printf("-1\n");  
        else if(n == 4){  
            printf("1 * 2\n");// 5 n*n  
            printf("5 + 3\n");// 6 5*n  
            printf("6 + 4\n");// 7 6*n  
        }  
        else if(n == 5){  
            printf("1 / 2\n");// 6 1  
            printf("6 / 3\n");// 7 1/5  
            printf("4 - 7\n");// 8 24/5  
            printf("5 * 8\n");// 9 24  
        }  
        else if(n == 6){  
            printf("1 + 2\n");  
            printf("7 + 3\n");  
            printf("8 + 4\n");  
            printf("9 + 5\n");  
            printf("10 - 6\n");  
        }  
        else if(n == 7){  
            printf("1 / 2\n");// 8 1  
            printf("3 * 4\n");// 9 n*n  
            printf("9 - 8\n");// 10 48  
            printf("5 + 6\n");// 11 2*n  
            printf("10 / 11\n");// 12 48/14  
            printf("12 * 7\n");// 13 24  
        }  
        else if(n == 8){  
            printf("1 - 2\n");// 9 0  
            printf("9 * 3\n");// 10 0  
            printf("10 * 4\n");// 11 0  
            printf("11 * 5\n");// 12 0  
            printf("12 + 6\n");// 13 n  
            printf("13 + 7\n");// 14 2*n  
            printf("14 + 8\n");// 15 3*n  
        }  
        else if(n == 9){  
            printf("1 / 2\n");// 10 1  
            printf("3 / 4\n");// 11 1  
            printf("5 / 6\n");// 12 1  
            printf("7 + 8\n");// 13 2*n  
            printf("13 + 9\n");// 14 3*n  
            printf("14 - 10\n");// 15 26  
            printf("15 - 11\n");// 16 25  
            printf("16 - 12\n");// 17 24  
        }  
        else if(n == 10){  
            printf("1 / 2\n");// 11 1  
            printf("3 / 4\n");// 12 1  
            printf("5 / 6\n");// 13 1  
            printf("7 / 8\n");// 14 1  
            printf("9 + 10\n");// 15 2*n  
            printf("11 + 12\n");// 16 2  
            printf("16 + 13\n");// 17 3  
            printf("17 + 14\n");// 18 4  
            printf("18 + 15\n");// 19 24  
        }  
        else if(n == 11){  
            printf("1 + 2\n");// 12 2*n  
            printf("3 / 4\n");// 13 1  
            printf("5 / 6\n");// 14 1  
            printf("12 + 13\n");// 15 23  
            printf("15 + 14\n");// 16 24  
            printf("7 - 8\n");// 17 0  
            for(int i = 9; i < 12; i++)  
                printf("%d * %d\n",i,i+8);  
            printf("16 + 20\n");  
        }  
        else if(n == 12){  
            printf("1 + 2\n");// 13 24  
            printf("3 - 4\n");// 14 0  
            for(i = 5; i < 13; i++)  
                printf("%d * %d\n",i,i+9);  
            printf("13 + 22\n");  
        }  
        else if(n == 13){  
            printf("1 + 2\n");// 14 26  
            printf("14 / 3\n");// 15 2  
            printf("4 / 5\n");// 16 1  
            printf("6 - 16\n");// 17 12  
            printf("15 * 17\n");// 18 24  
            printf("7 - 8\n");// 19 0  
            for(i = 9; i < 14; i++)  
                printf("%d * %d\n",i,i+10);  
            printf("18 + 24\n");  
        }  
        else if(n == 14){  
            printf("1 / 2\n");// 15 1  
            printf("3 / 4\n");// 16 1  
            printf("5 - 15\n");// 17 13  
            printf("17 - 16\n");// 18 12  
            printf("6 + 7\n");// 19 28  
            printf("19 / 8\n");// 20 2  
            printf("20 * 18\n");// 21 24  
            printf("9 - 10\n");// 22 0  
            for(i = 11; i < 15; i++)  
                printf("%d * %d\n",i,i+11);  
            printf("21 + 26\n");  
        }  
        else{  
            printf("1 + 2\n");// n+1 2*n  
            printf("3 + 4\n");// n+2 2*n  
            printf("5 + 6\n");// n+3 2*n  
            printf("7 + 8\n");// n+4 2*n  
            printf("%d + 9\n",n+1);// n+5 3*n  
            printf("%d / 10\n",n+2);// n+6 2  
            printf("%d / 11\n",n+3);// n+7 2  
            printf("%d / 12\n",n+4);// n+8 2  
            printf("%d / 13\n",n+5);// n+9 3  
            printf("%d * %d\n",n+6,n+7);// n+10 4  
            printf("%d * %d\n",n+8,n+9);// n+11 8  
            printf("%d * %d\n",n+10,n+11);// n+12 24  
            printf("14 - 15\n");  
            int now = n+13;  
            for(i = 16; i <= n; i++,now++)  
                printf("%d * %d\n",i,now);  
            printf("%d + %d\n",n+12,now);  
        }  
    }  
    return 0;  
}

10.JRY is Fighting

有待更新。。。