Move to dormitory 1421

# Include <iostream> # include <algorithm> using namespace STD; # define min (a, B) (a <B? A: B) # define INF 2100000000int DP [2001] [1001]; // The first subscript (2001) indicates int main () {int N; // The number of items int K; // The number of pairs int A [2001]; // array a is first used for the quality of each item, and then used to save the square difference. Int I; // row Int J; // column while (scanf ("% d", & N, & K )! = EOF) {for (I = 1; I <= N; ++ I) {scanf ("% d", & A [I]);} sort (a + 1, A + 1 + n); // sort the numbers from small to large. // calculate the squared difference of the numbers of adjacent pairs for (I = 1; I <N; ++ I) {// place the first squared difference in a [1], and the last one in a [n-1]; A total of N-1 square differences a [I] = (a [I + 1]-A [I]) * (a [I + 1]-A [I]);} /* initialize the DP array */for (I = 0; I <= N; I ++) // 0 rows to N rows for (j = 1; j <= K; j ++) // 1 column to k column DP [I] [J] = inf; // initialize two-dimensional array DP [I] [J] for (I = 0; I <= N; I ++) DP [I] [0] = 0; // The first column is initialized to 0/* formula: DP [I] [J] = min (DP [I-2] [J-1] + A [I-1], DP [I-1] [J]); */For (I = 2; I <= N; ++ I) {// note that I must <= N // select 2 to 3, 4 to J (2 * k <= N) pairs. For (j = 1; 2 * j <= I; ++ J) {// DP [I] [J]: front I take J pair // DP [I-2] [J-1] + A [I-1]: Front I-2 take J-1 pair, finally DP [I] [J] = min (DP [I-2] [J-1] + A [I-1], DP [I-1] [J]); // A [I-1] is the last squared difference // DP [0] [0]} // n total, select K pairs. Printf ("% d \ n", DP [N] [k]);} return 0 ;}