hdu 4391

          题目链接

  典型的sqrt(n)分块题目， 不过是个插段问段， 做法还是大同小异。。。。

#include <iostream>#include <cstring>#include <algorithm>#include <cstdio>#include <cstdlib>using namespace std;const int sz = 400;inline int readint() {char c = getchar();while (!isdigit(c)) c = getchar();int x = 0;while (isdigit(c)) {x = x * 10 + c - '0';c = getchar();}return x;}struct Block {int A[300][sz + 1], B[300][sz + 1];int size[305];int lazy[305];int n, row;void init(int n) {this->n = n;row = 0;memset(size, 0, sizeof(size));int r = 0, c = 0;for (int i = 0; i < n; i++) {scanf("%d", &A[r][c]);B[r][c] = A[r][c];size[r]++;c++;if (c == sz) {c = 0;r++;}}row = r + 1;for (int i = 0; i < row; i++) {sort(B[i], B[i] + size[i]);lazy[i] = -1;}}void modify(int l, int r, int x) {int r1 = l / sz, r2 = r / sz;int c1 = l % sz, c2 = r % sz;if (r1 == r2) {if (lazy[r1] == -1) {while (c1 <= c2) {A[r1][c1] = x;c1++;}}else {fill(A[r1], A[r1] + size[r1], lazy[r1]);while (c1 <= c2) {A[r1][c1] = x;c1++;}lazy[r1] = -1;}copy(A[r1], A[r1] + size[r1], B[r1]);sort(B[r1], B[r1] + size[r1]);}else {int tmp = size[r1];if (lazy[r1] == -1) {while (c1 < tmp) {A[r1][c1] = x;c1++;}copy(A[r1], A[r1] + size[r1], B[r1]);sort(B[r1], B[r1] + size[r1]);}else {fill(A[r1], A[r1] + size[r1], lazy[r1]);while (c1 < tmp) {A[r1][c1] = x;c1++;}lazy[r1] = -1;copy(A[r1], A[r1] + size[r1], B[r1]);sort(B[r1], B[r1] + size[r1]);}r1++;if (lazy[r2] == -1) {while (c2 >= 0) {A[r2][c2] = x;c2--;}copy(A[r2], A[r2] + size[r2], B[r2]);sort(B[r2], B[r2] + size[r2]);}else {fill(A[r2], A[r2] + size[r2], lazy[r2]);while (c2 >= 0) {A[r2][c2] = x;c2--;}lazy[r2] = -1;copy(A[r2], A[r2] + size[r2], B[r2]);sort(B[r2], B[r2] + size[r2]);}while (r1 < r2) {lazy[r1] = x;r1++;}}}int query(int l, int r, int x) {int r1 = l / sz, r2 = r / sz;int c1 = l % sz, c2 = r % sz;int res = 0;if (r1 == r2) {if (lazy[r1] == -1) {while (c1 <= c2) {if (A[r1][c1] == x) res++;c1++;}}else {res += lazy[r1] == x ? c2 - c1 + 1 : 0;}}else {int tmp = size[r1];if (lazy[r1] == -1) {while (c1 < tmp) {if (A[r1][c1] == x) res++;c1++;}}else {res += lazy[r1] == x ? tmp - c1 : 0;}r1++;if (lazy[r2] == -1) {while (c2 >= 0) {if (A[r2][c2] == x) res++;c2--;}}else {res += lazy[r2] == x ? c2 + 1 : 0;}while (r1 < r2) {if (lazy[r1] == -1)res += upper_bound(B[r1], B[r1] + size[r1], x) - lower_bound(B[r1], B[r1] + size[r1], x);elseres += lazy[r1] == x ? size[r1] : 0;r1++;}}return res;}}sol;int main() {int n, m, c, l, r, op;while (~scanf("%d%d", &n, &m)) {sol.init(n);while (m--) {//op = readint(), l = readint(), r = readint(), c = readint();scanf("%d%d%d%d", &op, &l, &r, &c);if (op == 1)sol.modify(l, r, c);elseprintf("%d\n", sol.query(l, r, c));}}return 0;}