题意简述
已知一个数列,你需要进行下面两种操作:
1.将某一个数加上x
2.求出某区间每一个数的和
代码
#include <cstdio>
using namespace std;
int n, m, N;
int a[1200001];
int main()
{
scanf("%d%d", &n, &m);
for (N = 1; N < n + 2; N <<= 1);
for (register int i = 1; i <= n; ++i)
scanf("%d", &a[i + N]);
for (register int i = N; --i; )
a[i] = a[i << 1] + a[i << 1 | 1];
for (register int i = 1; i <= m; ++i)
{
int opt, x, y, ans = 0;
scanf("%d%d%d", &opt, &x, &y);
if (opt == 1) for (register int j = x + N; j; j >>= 1) a[j] += y;
if (opt == 2)
{
for (register int j = x + N - 1, k = y + N + 1; j ^ k ^ 1; j >>= 1, k >>= 1)
{
if (~j & 1) ans += a[j ^ 1];
if ( k & 1) ans += a[k ^ 1];
}
printf("%d
", ans);
}
}
}