int d_min[maxn][maxm], d_max[maxn][maxm];//值
int minpos[maxn][maxm], maxpos[maxn][maxm];//下标
//预处理区间最大最小值
void RMQ_init(int n){
int i, j;
for (i = 1; i <= n; i++){
d_min[i][0] = a[i];
d_max[i][0] = a[i];
}
for (j = 1; (1 << j) <= n; j++)
for (i = 1; i + j - 1 <= n; i++){
d_min[i][j] = min(d_min[i][j - 1], d_min[i + (1 << (j - 1))][j - 1]);
d_max[i][j] = max(d_max[i][j - 1], d_max[i + (1 << (j - 1))][j - 1]);
}
}
//查询区间最小值
int RMQ_min(int l, int r){
int k = 0;
while ((1 << (k + 1)) <= r - l + 1) k++;
return min(d_min[l][k], d_min[r - (1 << k) + 1][k]);
}
//查询区间最大值
int RMQ_max(int l, int r){
int k = 0;
while ((1 << (k + 1)) <= r - l + 1) k++;
return max(d_max[l][k], d_max[r - (1 << k) + 1][k]);
}
//预处理区间最大最小值的下标
void RMQ_pos_init(int n, int b[]){
int i, j;
for (i = 1; i <= n; i++) {
maxpos[i][0] = i;
minpos[i][0] = i;
}
for (j = 1; (1 << j) <= n; j++)
for (i = 1; i + (1 << j) - 1 <= n; i++){
minpos[i][j] = b[minpos[i][j - 1]] < b[minpos[i + (1 << (j - 1))][j - 1]] ? minpos[i][j - 1] : minpos[i + (1 << (j - 1))][j - 1];
maxpos[i][j] = b[maxpos[i][j - 1]] > b[maxpos[i + (1 << (j - 1))][j - 1]] ? maxpos[i][j - 1] : maxpos[i + (1 << (j - 1))][j - 1];
}
}
//查询区间最大值的下标
int RMQ_pos_max(int s, int v, int b[]){
int k = (int)(log((v - s + 1)*1.0) / log(2.0));
return b[maxpos[s][k]] > b[maxpos[v - (1 << k) + 1][k]] ? maxpos[s][k] : maxpos[v - (1 << k) + 1][k];
}
//查询区间最小值的下标
int RMQ_pos_min(int s, int v, int b[]){
int k = (int)(log((v - s + 1)*1.0) / log(2.0));
return b[minpos[s][k]] < b[minpos[v - (1 << k) + 1][k]] ? minpos[s][k] : minpos[v - (1 << k) + 1][k];
}
/*----------------------------------------------------------------*/
/*----------------------------------------------------------------*/
RMQ模板
最新推荐文章于 2022-03-26 21:08:54 发布