/* 二维的树状数组: 更新某个元素时: NO.1:c[n1],c[n2],c[n3],....,c[nm]; 当中n1 = i,n(i+1) = ni+lowbit(ni); nm+lowbit(nm)的值应该大于元素个数N。 NO.2:sum(k)=c[n1]+c[n2]+...+c[nm]; 当中nm=k,n(i-1)=ni-lowbit(ni); n1-lowbit(n1)的值应该小于0 ---------------------------------------------------------------------- 用二维的c[i][j]存储长条的和。。。、 --------------------------------------- 元素的值加一个数: void update(int x, int y, int a) { for(int i=x; i<=s; i+=lowbit(i)) { for(int j=y; j<=s; j+=lowbit(j)) c[i][j] += a; } } --------------------------------------------------- int sum(int x, int y)矩阵0到x和0到y的元素和 { int ret = 0; for(int i=x; i>0; i-=lowbit(i)) { for(int j=y; j>0; j-=lowbit(j)) ret += c[i][j]; } return ret; } ------------------------------------------------ */ #include <iostream> #include <cstdio> #include <cstring> #define INF 0x3f3f3f3f using namespace std; int op,s; int x,y,a; int l,b,r,t; int c[1050][1050]; int lowbit(int x) { return x & (-x); } void update(int x, int y, int a) { for(int i=x; i<=s; i+=lowbit(i)) { for(int j=y; j<=s; j+=lowbit(j)) c[i][j] += a; } } int sum(int x, int y) { int ret = 0; for(int i=x; i>0; i-=lowbit(i)) { for(int j=y; j>0; j-=lowbit(j)) ret += c[i][j]; } return ret; } int main() { //freopen("input.txt","r",stdin); while(1) { scanf("%d",&op); if(op == 0) { scanf("%d",&s); memset(c, 0, sizeof(c)); } if(op == 1) { scanf("%d%d%d",&x,&y,&a); update(x+1, y+1, a); } if(op == 2) { scanf("%d%d%d%d",&l, &b,&r,&t); l++; b++; r++; t++; printf("%d\n",sum(r, t) - sum(r, b-1) - sum(l-1, t) + sum(l-1, b-1) ); } if(op == 3) return 0; } }
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快。。。。。