C++ BIT::sum方法代码示例

int main(void){
    int T;
    scanf("%d", &T);
    while(T--) {
        scanf("%d", &n);
        int maxa = 0;
        for(int i = 1; i <= n; i++) {
            scanf("%d", a+i);
            maxa = maxa > a[i] ? maxa: a[i];
        }

        BIT t;
        t.resize(maxa);
        t.clear();
        for(int i = 1; i <= n; i++) {
            t.add(a[i], 1);
            c[i] = t.sum(a[i] - 1);
        }
        t.clear();
        for(int i = n; i > 0; i--) {
            t.add(a[i], 1);
            d[i] = t.sum(a[i] - 1);
        }

        long long ans = 0;
        for(int i = 1; i <= n; i++) {
            ans += (long long)c[i]*(n-i-d[i]) + (long long)(i-c[i]-1)*d[i];
        }
        printf("%lld\n", ans);
    }
    return 0;
}

int main() {
	ios_base::sync_with_stdio(false);

	int n, m, k;
	int x, y;

	cin >> n >> m >> k;	

	op.init(m+10);
	a.init(n+10);

	for (int i=1; i<=n; ++i) {
		cin >> x;
		a.add_interval(i, i, x);
	}
	for (int i=1; i<=m; ++i) cin >> l[i] >> r[i] >> d[i];
	for (int i=0; i<k; ++i) {
		cin >> x >> y;	
		op.add_interval(x, y, 1);
	}
	for (int i=1; i<=m; ++i) a.add_interval(l[i], r[i], op.sum(i)*d[i]);
	for (int i=1; i<=n; ++i) cout << a.sum(i) << (i < n ? " " : "\n");

	return 0;
}

void CDQ(int nl, int nr)
{
	if(nl>=nr) return;
	int mid=(nl+nr)>>1;
	CDQ(nl, mid); CDQ(mid+1,nr);
	
	int tl=mid;
	for(int tr=nr; tr>mid; tr--)
	{
		while(tl>=nl && arry[tl].l >= arry[tr].l)
		{
			bit.add( arry[tl].r, arry[tl].v);
			tl--;
		}
		ans[ arry[tr].t ] += bit.sum( arry[tr].r );
	}
	for(int i=mid; i>tl; i--) bit.add( arry[i].r, -arry[i].v);
	
	tl=nl;
	int tp=nl;
	for(int tr=mid+1; tr<=nr; tr++)
	{
		while(tl<=mid && arry[tl].l < arry[tr].l) temp[tp++] = arry[tl++];
		temp[tp++] = arry[tr];
	}
	while(tl<=mid) temp[tp++] = arry[tl++];
	
	for(int i=nl; i<=nr; i++) arry[i]=temp[i];
}

void solve()
{
    ll ans = 0;
    BIT b;
    for (int j = 0; j < n; j++) {
	ans += j - b.sum(b.a[j]);
    }
}

int calc(int p) {
  printf("calc(%d)\n", p);
  int cnt[20];
  memset(cnt, 0, sizeof cnt);
  int max_power = 0;
  memset(power, 0, sizeof power);
  for(int i = 0; i < n; i++) {
    int num = v[i];
    while(num % p == 0) {
      power[i]++;
      num /= p;
    }
    cnt[power[i]]++;
    max_power = max(max_power, power[i]);
  }
  printf("max_power=%d ", max_power);
  bit.init();
  for(int i = 1; i <= max_power; i++) {
    bit.add(i, cnt[i]);
  }
  int ans = 0;
  int cur = p;
  int base[20];
  for(int i = 1; cur <= maxa; i++) {
    base[i] = cur;
    cur = (cur * 1LL * p) % mod;
  }
  for(int i = 0; i < n; i++) {
    if(power[i] == 0)
      continue;
    printf("total(%d - %d)=%d ", bit.sum(max_power), bit.sum(power[i] - 1), total(bit.sum(max_power) - bit.sum(power[i] - 1)));
    ans = (ans + (base[power[i]] * 1LL * total(bit.sum(max_power) - bit.sum(power[i] - 1))) % mod) % mod;
    printf("i=%d ans=%d ", i, ans);
    for(int j = power[i] - 1; j >= 1; j--) {
      ans = (ans + (base[j] * 1LL * total(cnt[j])) % mod) % mod;
      printf("cnt[%d]=%d ans=%d ", j, cnt[j], ans);
    }
    printf("ans=%d\n", ans);
    cnt[power[i]]--;
    bit.add(power[i], -1);
  }
  return ans;
}

	int dfs(int c, int k) {
		int iv = bit.sum(1000) - bit.sum(vertex[c]);
		if (k <= 1) {
			return iv;
		}

		visited[c] = 1;
		bit.add(vertex[c], 1);

		int res = 1 << 30;

		if (k > 1) {
			for (int v : edge[c]) {
				if (!visited[v]) {
					res = min(res, iv + dfs(v, k - 1));
				}
			}
		}

		bit.add(vertex[c], -1);
		visited[c] = 0;
		return res;
	}

int main() {

  int x, r, h;
  int a, b;

  scanf("%d%d", &N, &Q);
  bit.init(MAX_X + MAX_H);
  for (int i = 0; i < N; i++) {
    scanf("%d%d%d", &x, &r, &h);
    for (int j = 0; j < h; j++) {
      bit.add(x + j + 1, (double)r * r * M_PI * h * 1.0/3.0 * (pow(h - j, 3) - pow(h - j - 1, 3)) / pow(h, 3));
    }
  }

  for (int i = 0; i < Q; i++) {
    scanf("%d%d", &a, &b);
    ans = bit.sum(b) - bit.sum(a);
    printf("%lf\n", ans);
  }

  return 0;

}

void solve(){
    if(!len){
        puts("Poor stack!");
        return;
    }
    b = BIT(ns);
    rep(i,ns) b.add(i,1);
    rep(i,ms){
        for(int j = k[i]-1; j >= 0; --j){
            int pos = b.find(a[j]);
            b.add(pos,-1);
        }
    }
    rep(i,ns) if(b.sum(i,i+1)) printf("%d", seq[i]);
    puts("");
}

int main(int argc, const char * argv[]) {
    int ff;
    int v1, v2, t;
    char query[20];
    BIT bit;
    scanf("%d", &ff);
    for (int tt = 1; tt <= ff; tt++) {
        printf("Case %d:\n", tt);
        int n;
        scanf("%d", &n);
        bit.build(n+1);
        for (int i = 1; i <= n; i++) {
            scanf("%d", &t);
            bit.modify(i, t);
        }
        bool fl = true;
        while (fl) {
            scanf("%s", query);
            switch (query[0]) {
                case 'Q':
                    scanf("%d %d", &v1, &v2);
                    printf("%d\n", bit.sum(v1, v2));
                    break;
                case 'A':
                    scanf("%d %d", &v1, &v2);
                    bit.modify(v1, v2);
                    break;
                case 'S':
                    scanf("%d %d", &v1, &v2);
                    bit.modify(v1, -v2);
                    break;
                case 'E':
                    fl = false;
                    break;
            }
        }
    }
}