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【模板】zoj2859_二維st表

#include <cstdio>
#include <algorithm>
#include <cmath>

using namespace std;

int stmin[301][301][9][9];

int n;//n行n列
int q;

void init_st(int n)
{
    int i, j, k1, k2;
    for(k1 = 0; k1 <= (int)log2(n); ++k1)
        for(k2 = 0; k2 <= (int)log2(n); ++k2)
    {
            if(!k1 && !k2) continue
; for(i = 1; i <= n; ++i) for(j = 1; j <= n; ++j) { int tag1 = i + (1<<k1) - 1; int tag2 = j + (1<<k2) - 1; if(tag1 > n || tag2 > n) continue; if(!k1) stmin[i][j][0][k2] = min(stmin[i][j][0][k2-1
], stmin[i][j+(1<<(k2-1))][0][k2-1]); else stmin[i][j][k1][k2] = min(stmin[i][j][k1-1][k2], stmin[i+(1<<(k1-1))][j][k1-1][k2]); } } } int query(int x1, int y1, int x2, int y2) { int k1 = log2(x2-x1+1); int k2 = log2(y2-y1+1); int t1 = min(stmin[x1][y1][k1][k2], stmin[x2-(1
<<k1)+1][y2-(1<<k2)+1][k1][k2]); int t2 = min(stmin[x1][y2-(1<<k2)+1][k1][k2], stmin[x2-(1<<k1)+1][y1][k1][k2]); int ret = min(t1, t2); return ret; } int main() { int i, j, x1, y1, x2, y2; int t; scanf("%d", &t); while(t--) { scanf("%d", &n); for(i = 1; i <= n; ++i) for(j = 1; j <= n; ++j) scanf("%d", &stmin[i][j][0][0]); init_st(n); scanf("%d", &q); while(q--) { scanf("%d %d %d %d", &x1, &y1, &x2, &y2); int ans = query(x1, y1, x2, y2); printf("%d\n", ans); } } return 0; }

降成三維儲存

#include <cstdio>
#include <algorithm>
#include <cmath>

using namespace std;

int n, q;
int st[301][301][10];

void init_st(int n)
{
    int i, j, k;
    for(k = 1; k <= (int)log2(n); ++k)
        for(i = 1; i <= n-(1<<k)+1; ++i)
            for(j = 1; j <= n-(1<<k)+1; ++j)
        {
            int t1 = min(st[i][j][k-1], st[i+(1<<(k-1))][j][k-1]);
            int t2 = min(st[i][j+(1<<(k-1))][k-1], st[i+(1<<(k-1))][j+(1<<(k-1))][k-1]);
            st[i][j][k] = min(t1, t2);
        }
}

int query(int x1, int y1, int x2, int y2)
{
    int k1 = log2(x2-x1+1);
    int k2 = log2(y2-y1+1);
    if(k1==k2) return min(st[x1][y1][k1], min(st[x2-(1<<k1)+1][y1][k1], min(st[x1][y2-(1<<k2)+1][k1], st[x2-(1<<k1)+1][y2-(1<<k2)+1][k1])));
    if(k1<k2)
    {
        int k = k1;
        int minret = 0x3f3f3f3f;
        for(int i = y1; i <= y2 - (1<<k) + 1; i += (1<<k))
            minret = min(minret, min(st[x1][i][k], st[x2-(1<<k)+1][i][k]));
        minret = min(minret, min(st[x1][y2-(1<<k)+1][k], st[x2-(1<<k)+1][y2-(1<<k)+1][k]));
        return minret;
    }
    int k = k2;
    int minret = 0x3f3f3f3f;
    for(int i = x1; i <= x2-(1<<k)+1; i += (1<<k))
        minret = min(minret, min(st[i][y1][k], st[i][y2-(1<<k)+1][k]));
    minret = min(minret, min(st[x2-(1<<k)+1][y1][k], st[x2-(1<<k)+1][y2-(1<<k)+1][k]));
    return minret;
}

int main()
{
    int i, j, t, q, x1, x2, y1, y2;
    scanf("%d", &t);
    while(t--)
    {
        scanf("%d", &n);
        for(i = 1; i <= n; ++i)
            for(j = 1; j <= n; ++j)
                scanf("%d", &st[i][j][0]);
        init_st(n);
        scanf("%d", &q);
        while(q--)
        {
            scanf("%d %d %d %d", &x1, &y1, &x2, &y2);
            int ans = query(x1, y1, x2, y2);
            printf("%d\n", ans);
        }
    }
    return 0;
}