Codeforces Round #301

http://codeforces.com/contest/540A. Combination Lock

n = input()
s1 = raw_input()
s2 = raw_input()
ans=0
for i in range(n):
    tmp1 = abs((int)(s1[i])-(int)(s2[i]))
    ans += min(tmp1, 10-tmp1)
print ans

B. School Marks

import java.util.Arrays;
import java.util.Scanner;

import javax.swing.plaf.synth.SynthScrollBarUI;

public class Test
{
    public static void main(String[] args)
    {
        Scanner sc = new Scanner(System.in);
        int n, k, p, x, y;
        n = sc.nextInt();
        k = sc.nextInt();
        p = sc.nextInt();
        x = sc.nextInt();
        y = sc.nextInt();
        int sum = 0, sum1 = 0, sum2 = 0;
        int[] a = new int[n];
        int[] b = new int[n];
        int l = 0;
        for(int i = 0; i < k; i++) {
            b[i] = sc.nextInt();
            sum += b[i];
            if(b[i] >= y)
                sum1++;
            else if(b[i] < y)
                sum2++;
        }
        Arrays.sort(b, 0, k);
        int ans1 = -1;
        if(sum2 > n/2) {
            
        }
        else if(sum1 > n/2) {
            sum += n-k;
            if(sum <= x) {
                for(int i = 0; i < n-k; i++) {
                    a[l++] = 1;
                }
            }
        }
        else {
            sum += n/2-sum2;
            sum += y*(n/2-sum1+1);
            if(sum <= x) {
                for(int i = 0; i < n/2-sum2; i++) {
                    a[l++] = 1;
                }
                for(int i = 0; i < n/2-sum1+1; i++) {
                    a[l++] = y;
                }
            }
        }
        if(l == 0) {
            System.out.println(-1);
        }
        else {
            for(int i = 0; i < l; i++) {
                System.out.println(a[i]);
            }
        }
    }
    
}

C. Ice Cave广搜

import java.util.LinkedList;
import java.util.Scanner;

public class Test {
    public static char[][] a;
    public static int[][] vis;
    public static int[][] dir = {{-1, 0}, {1, 0}, {0, 1}, {0, -1}};
    public static int n, m;
    static class node {
        int x, y;
        public node(int x, int y) {
            this.x = x;
            this.y = y;
        }
    }
    
    public static boolean BFS(int s1, int e1, int s2, int e2) {
        LinkedList Q = new LinkedList<>();
        Q.add(new node(s1, e1));
        while(!Q.isEmpty()) {
            node u = Q.removeFirst();
            if(u.x == s2 && u.y == e2 && a[u.x][u.y] == '*') {
                return true;
            }
            for(int i = 0; i < 4; i++) {
                int x = u.x + dir[i][0];
                int y = u.y + dir[i][1];
                if(x < 0 || x >= n || y < 0 || y >= m) {
                    continue;
                }
                if(a[x][y] == '.') {
                    Q.add(new node(x, y));
                    a[x][y] = 'X';
                }
                else if(x == s2 && y == e2) {
                    Q.add(new node(x, y));
                    a[x][y] = '*';
                }
            }
        }
        return false;
    }
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        n = sc.nextInt();
        m = sc.nextInt();
        a = new char[n][m];
        sc.nextLine();
        for(int i = 0; i < n; i++) {
            a[i] = sc.nextLine().toCharArray();
        }
        int s1 = sc.nextInt(), e1 = sc.nextInt();
        int s2 = sc.nextInt(), e2 = sc.nextInt();
        vis = new int[n][m];
        if(BFS(s1-1, e1-1, s2-1, e2-1)) {
            System.out.println("YES");
        }
        else {
            System.out.println("NO");
        }
    }
}

D. Bad Luck Island概率DP

import java.util.LinkedList;
import java.util.Scanner;

public class Test {
	static int r, s, p;
	static double dp[][][];
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		r = sc.nextInt();
		s = sc.nextInt();
		p = sc.nextInt();
		dp = new double[r+10][s+10][p+10];
		dp[r][s][p] = 1.0;
		for(int i = r; i >= 0; i--) {
			for(int j = s; j >= 0; j--) {
				for(int k = p; k >=0; k--) {
					//if(i+j == 0 || j+k == 0 || i+k == 0)
						//continue;
					if(i == r && j == s && k == p)
						continue;
					dp[i][j][k] = 0;
					if(i > 0) {
						dp[i][j][k] += dp[i][j+1][k]*i*(j+1)/(i*(j+1)+(j+1)*k+i*k);
					}
					if(j > 0) {
						dp[i][j][k] += dp[i][j][k+1]*j*(k+1)/(i*j+j*(k+1)+i*(k+1));
					}
					if(k > 0) {
						dp[i][j][k] += dp[i+1][j][k]*k*(i+1)/((i+1)*j+j*k+(i+1)*k);
					}
				}
			}
		}
		double ans1 = 0, ans2 = 0, ans3 = 0;
		for(int i = 1; i <= r; i++) {
			ans1 += dp[i][0][0];
		}
		for(int i = 1; i <= s; i++) {
			ans2 += dp[0][i][0];
		}
		for(int i = 1; i <= p; i++) {
			ans3 += dp[0][0][i];
		}
		System.out.println(ans1+" "+ans2+" "+ans3);
	}
}

E. Infinite Inversions