zkw 线段树

优秀的 zkw 线段树讲解：《线段树的扩展之浅谈 zkw 线段树》

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存一份模板代码（区间修改、区间查询）：

/* zkw Segment Tree
 * Au: GG
 */
#include <cstdio>
typedef long long ll;
const int N=1e5+3;
int n, m, zkw; ll t[N<<2], laz[N<<2];

inline void update(int x, int y, ll val) {
    ll l=0, r=0, f=1;
    for (x+=zkw-1, y+=zkw+1; x^y^1; x>>=1, y>>=1, f<<=1) {
        t[x]+=val*l, t[y]+=val*r;
        if (~x&1) laz[x^1]+=val, t[x^1]+=val*f, l+=f;
        if (y&1) laz[y^1]+=val, t[y^1]+=val*f, r+=f;
    }
    for (; x; x>>=1, y>>=1) t[x]+=val*l, t[y]+=val*r;
}

inline ll query(int x, int y) {
    ll res=0, l=0, r=0, f=1;
    for (x+=zkw-1, y+=zkw+1; x^y^1; x>>=1, y>>=1, f<<=1) {
        if (laz[x]) res+=laz[x]*l; 
        if (laz[y]) res+=laz[y]*r;
        if (~x&1) res+=t[x^1], l+=f;
        if (y&1) res+=t[y^1], r+=f;
    }
    for (; x; x>>=1, y>>=1) res+=laz[x]*l, res+=laz[y]*r;
    return res;
}

int main() {
    scanf("%d%d", &n, &m);
    for (zkw=1; zkw<=n+1; zkw<<=1);
    for (int i=zkw+1; i<=zkw+n; i++) scanf("%lld", t+i);
    for (int i=zkw-1; i>0; --i) t[i]=t[i<<1]+t[i<<1|1];
    while (m--) {
        int opt, a, b; ll c; scanf("%d%d%d", &opt, &a, &b);
        if (opt<2) scanf("%lld", &c), update(a, b, c); 
        else printf("%lld
", query(a, b));
    }
    return 0;
}