题目描述
思路
update是从(x,y)处往下更新,sum是求(x,y)到(0, 0)的和
代码
#include <cstdio>
#include <cstring>
int n, m;
long long arr[5005][5005];
int lowbit[5005];
void update(int x, int y, int z) {
while (x <= n) {
int j = y;
while (j <= m) {
arr[x][j] += z;
j += lowbit[j];
}
x += lowbit[x];
}
}
long long sum(int x, int y) {
long long res = 0;
while (x) {
int j = y;
while (j) {
res += arr[x][j];
j -= lowbit[j];
}
x -= lowbit[x];
}
return res;
}
int main() {
scanf("%d %d", &n, &m);
for (int i = 1; i < 5005; ++i) lowbit[i] = i & (-i);
int a, b, c, d, e;
while (scanf("%d", &a) != EOF) {
if (a == 1) {
scanf("%d %d %d", &b, &c, &d);
update(b, c, d);
} else {
scanf("%d %d %d %d", &b, &c, &d, &e);
printf("%lld\n", sum(d, e) - sum(b - 1, e) - sum(d, c - 1) + sum(b - 1, c - 1));
}
}
return 0;
}