poj 3468——A Simple Problem with Integers

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#include<iostream>#include<cstdio>using namespace std;#define maxn 100005#define LL __int64#define ls (rt<<1)#define rs (rt<<1|1)#define mid ((t[rt].l+t[rt].r)>>1)LL n,m;struct tree{LL l,r;LL sum;LL lazy;}t[maxn<<2];void pushup(LL rt){t[rt].sum=t[ls].sum+t[rs].sum;}void pushdown(LL rt){if(t[rt].lazy!=0){t[rs].sum+=t[rt].lazy*(t[rs].r-t[rs].l+1);t[ls].sum+=t[rt].lazy*(t[ls].r-t[ls].l+1);t[ls].lazy+=t[rt].lazy;t[rs].lazy+=t[rt].lazy;t[rt].lazy=0;return;}}void build(LL rt,LL l,LL r){t[rt].l=l,t[rt].r=r,t[rt].lazy=0;if(l==r){LL x;scanf("%I64d",&x);t[rt].sum=x;return;}build(ls,l,mid);build(rs,mid+1,r);pushup(rt);}LL query(LL rt,LL l,LL r){if(t[rt].l==l&&t[rt].r==r)return t[rt].sum;pushdown(rt);if(r<=mid)return query(ls,l,r);else if(l>mid)return query(rs,l,r);elsereturn query(ls,l,mid)+query(rs,mid+1,r);}void add(LL rt,LL l,LL r,LL val){if(t[rt].l==l&&t[rt].r==r){t[rt].sum+=val*(r-l+1);t[rt].lazy+=val;return ;}pushdown(rt);if(r<=mid)add(ls,l,r,val);else if(l>mid)add(rs,l,r,val);else{add(ls,l,mid,val);add(rs,mid+1,r,val);}pushup(rt);}int main(){while(~scanf("%I64d%I64d",&n,&m)){build(1,1,n);char s[10];while(m--){scanf("%s",s);if(s[0]=='Q'){LL l,r;scanf("%I64d%I64d",&l,&r);printf("%I64d\n",query(1,l,r));}else{LL l,r,val;scanf("%I64d%I64d%I64d",&l,&r,&val);if(val==0)continue;add(1,l,r,val);}}}return 0;}