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https://ac.nowcoder.com/acm/contest/332/E
C++版本一
題解:二維前綴和DP
dp[i][j]代表從(1,1)到(i,j)的所有低于d的數(shù)量
/* *@Author: STZG *@Language: C++ */ #include <bits/stdc++.h> #include<iostream> #include<algorithm> #include<cstdlib> #include<cstring> #include<cstdio> #include<string> #include<vector> #include<bitset> #include<queue> #include<deque> #include<stack> #include<cmath> #include<list> #include<map> #include<set> //#define DEBUG #define RI register int using namespace std; typedef long long ll; //typedef __int128 lll; const int N=100000+10; const int MOD=1e9+7; const double PI = acos(-1.0); const double EXP = 1E-8; const int INF = 0x3f3f3f3f; int t,n,m,k,q,x,y,x2,y2,d; int ans,cnt,flag,temp; char str;int main() { #ifdef DEBUGfreopen("input.in", "r", stdin);//freopen("output.out", "w", stdout); #endifscanf("%d%d%d",&n,&m,&d);int a[n+10][m+10];int dp[n+10][m+10];memset(dp,0,sizeof(dp));for(int i=1;i<=n;i++){for(int j=1;j<=m;j++){scanf("%d",&a[i][j]);if(a[i][j]>=d){dp[i][j]++;}dp[i][j]=dp[i][j]+dp[i-1][j]+dp[i][j-1]-dp[i-1][j-1];}}scanf("%d",&t);while(t--){scanf("%d%d%d%d",&x,&y,&x2,&y2);cout << dp[x2][y2]-dp[x-1][y2]-dp[x2][y-1]+dp[x-1][y-1]<< endl;}//cout << "Hello world!" << endl;return 0; }?
總結(jié)