## Monday, August 29, 2016

### TopCoder SRM 568 BallsSeparating

TopCoder SRM 568 BallsSeparating | 书影博客
There are N boxes numbered from 0 to N-1, inclusive. For each i, box i contains red[i] red balls, green[i] green balls, and blue[i] blue balls.
Fox Ciel wants to separate the balls by colors. In each operation, she can pick a single ball from some box and put it into another box. She considers the balls to be separated if no box contains balls of more than one color.
Return the minimal number of operations required to separate the balls. If this is impossible, return -1.
Definition

Class: BallsSeparating
Method: minOperations
Parameters: int[], int[], int[]
Returns: int
Method signature: int minOperations(int[] red, int[] green, int[] blue)
(be sure your method is public)

Constraints
- red, green and blue will each contain between 1 and 50 elements, inclusive.
- red, green and blue will contain the same number of elements.
- Each element of red, green and blue will be between 1 and 1,000,000, inclusive.

'
public static void main(String[] args) { BallsSeparating bs = new BallsSeparating(); int[] red = {842398, 491273, 958925, 849859, 771363, 67803, 184892, 391907, 256150, 75799}; int[] green = {268944, 342402, 894352, 228640, 903885, 908656, 414271, 292588, 852057, 889141}; int[] blue = {662939, 340220, 600081, 390298, 376707, 372199, 435097, 40266, 145590, 505103}; int ans = bs.minOperations(red, green, blue); System.out.println(ans); } public int minOperations(int[] red, int[] green, int[] blue) { int boxNum = red.length; if (boxNum < 3) { return -1; } int dp[][] = new int[8][boxNum + 1]; for (int i = 0; i < 8; i++) { for (int j = 0; j <= boxNum; j++) { dp[i][j] = -1; } } dp[0][0] = 0; for (int i = 1; i <= boxNum; i++) { int r = red[i - 1]; int g = green[i - 1]; int b = blue[i - 1]; for (int k = 0; k < 3; k++) { for (int j = 0; j < 8; j++) { //BGR int code = getCode(j,k); int val = getValue(r,g,b,k); if (dp[j][i - 1] >= 0) { if (dp[code][i] < 0) dp[code][i] = dp[j][i - 1] + val; else dp[code][i] = Math.min(dp[code][i], dp[j][i - 1] + val); } System.out.print(dp[code][i] + " "); } System.out.println(); } System.out.println(); } return dp[7][boxNum]; } public int getValue(int r, int g, int b, int color) { if (color == 0) //B return r + g; else if (color == 1) //G return r + b; else //R return g + b; } //210 //RGB public int getCode(int curCode, int color) { return curCode | (1 << color); }