Create 2019-C-B.cpp

RMQ

Author: tmp-coder

Diff for: kick-start/2019-C-B.cpp

@@ -0,0 +1,80 @@
+#include<bits/stdc++.h>
+
+using namespace std;
+
+#define ms(x,v) memset(x,(v), sizeof(x))
+#define msn(x,v,n) memset(x,(v),sizeof(x[0]) * n)
+#define INF 0x3f3f3f3f
+
+typedef long long LL;
+typedef pair<int,int> PII;
+
+const int MAXN = 300 + 3;
+
+
+struct RMQ{
+    int minA[10][MAXN],maxA[10][MAXN];
+    void init(const int * a,int n){
+        for(int i=0 ; i<n ; ++i){
+            minA[0][i] = maxA[0][i] = a[i];
+        }
+        for(int j=1 ; (1<<j)<=n ; ++j)
+            for(int i=0 ; i+(1<<(j-1)) <n ; ++i){
+                minA[j][i] = min(minA[j-1][i],minA[j-1][i+(1<<(j-1))]);
+                maxA[j][i] = max(maxA[j-1][i],maxA[j-1][i+(1<<(j-1))]);
+            }
+    }
+
+    pair<int,int> query_min_max(int l,int r){
+        if(l>r)return PII(0,0);
+        int k=0;
+        while((1<<(k+1)) <= r-l+1) ++k;
+        return make_pair(min(minA[k][l],minA[k][r-(1<<k)+1]),max(maxA[k][l],maxA[k][r-(1<<k)+1]));
+    }
+
+};
+
+RMQ rmq[MAXN];
+int rr,cc,kk;
+int aux[MAXN];
+
+int solve(){
+    int ans =0;
+    for(int l = 0 ; l < cc ; ++l)
+        for(int r = l ; r < cc ; ++r){
+            int len = 0;
+            int cur_len = 0;
+            for(int row = 0; row < rr ;  ++row){
+                auto minmax = rmq[row].query_min_max(l,r);
+                if( minmax.second - minmax.first <=kk){
+                    cur_len ++;
+                    if(len < cur_len)len = cur_len;
+                }else cur_len = 0;
+            }
+            ans = max(ans , len * (r -l+1));
+        }
+    return ans;
+}
+
+int main(int argc, char const *argv[])
+{   
+    ios :: sync_with_stdio(0);
+    cin.tie(0);
+    std::cout.precision(8);
+    std::cout.setf( std::ios::fixed, std:: ios::floatfield );
+    int T;
+    cin >> T;
+
+    for(int t =1;  t <= T ; ++t)
+    {   
+        cin >> rr >> cc >> kk;
+        for(int i=0 ; i< rr ; ++i){
+            for(int j=0 ; j< cc ; ++j)
+                cin >> aux[j];
+            rmq[i].init(aux,cc);
+        }
+        cout << "Case #"<<t << ": " << solve() << "\n";
+    }
+
+    return 0;
+}