Ultraviolet A 1406-A Sequence of Numbers (tree array)
Link to the question: A 1406-A Sequence of Numbers
There are two operations for a given number of n:
- Q x: calculates the number of values equal to or greater than zero for 2x.
- C x: Add x to each number.
Outputs the sum of all Q operations.Solution: Because x is 15 at the maximum, 16 tree arrays are opened. fenx [x] records the situation where every number modulo is 2x + 1, then there is an add value to mark the total amount added. Determine the range of the original number based on the add value.
#include
#include
#include using namespace std;#define lowbit(x) ((x)&(-x))const int maxn = 1<<16;const int maxr = 16;int base[maxr+5], fenx[maxr+5][maxn+5];int N, add;int query_treeArr (int* bit, int x) { int ret = 0; while (x) { ret += bit[x]; x -= lowbit(x); } return ret;}void insert_treeArr (int* bit, int x, int v) { while (x <= maxn) { bit[x] += v; x += lowbit(x); }}void init () { add = 0; for (int i = 0; i < maxr; i++) memset(fenx, 0, sizeof(fenx)); int x; for (int i = 0; i < N; i++) { scanf("%d", &x); for (int j = 1; j <= maxr; j++) { insert_treeArr(fenx[j-1], x % base[j] + 1, 1); } }}long long solve () { long long ret = 0; int x; char order[5]; while (scanf("%s", order) == 1 && strcmp(order, "E")) { scanf("%d", &x); if (order[0] == 'Q') { int have = add % base[x]; if (add & base[x]) { ret += query_treeArr(fenx[x], base[x] - have); ret += query_treeArr(fenx[x], base[x+1]) - query_treeArr(fenx[x], base[x+1] - have); } else ret += query_treeArr(fenx[x], base[x+1] - have) - query_treeArr(fenx[x], base[x] - have); } else add = (add + x) % base[16]; } return ret;}int main () { int cas = 1; base[0] = 1; for (int i = 1; i <= maxr; i++) base[i] = base[i-1] * 2; while (scanf("%d", &N) == 1 && N != -1) { init(); printf("Case %d: %lld\n", cas++, solve()); } return 0;}