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題面

#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#define LL long long

using namespace std;
//輸出優化  begin 
inline void wprint(int x){
	if (x>9)	wprint(x/10);
	putchar(x%10+'0');
}

inline void print(int x){
	if (x<0) x=-x,putchar('-');
	wprint(x);
	putchar('\n');
}
//輸出優化	end 
//讀入優化	begin 
inline int wread(){
	char c(getchar());int wans(0),flag(1);
	while (c<'0'||c>'9'){if (c=='-') flag=-1;c=getchar();}
	while (c>='0'&&c<='9'){wans=(wans<<3)+(wans<<1)+(c^48);c=getchar();}
	return wans*=flag;
}

inline LL ll_wread(){
	char c(getchar());LL wans((LL)0),flag((LL)1);
	while (c<'0'||c>'9'){if (c=='-') flag=-1;c=getchar();}
	while (c>='0'&&c<='9'){wans=(wans<<3)+(wans<<1)+(c^48);c=getchar();}
	return wans*=flag;
} 
//讀入優化	end 

struct node{int l,r,len;LL ans,lazy1;}e[400004];

int n,m;

void make_tre(int a,int l,int r){
	e[a].l=l; e[a].r=r; e[a].ans=e[a].lazy1=0;
	if (l==r){e[a].ans=ll_wread(); e[a].len=(LL)1; return ;}
	int mid( l+r >>1 ),lson(a<<1),rson(a<<1|1);
	make_tre(lson, l, mid); make_tre(rson, mid+1, r);
	e[a].ans=e[lson].ans + e[rson].ans;
	e[a].len=e[lson].len + e[rson].len;
}

void xia_fang(int a){
	int lson(a<<1),rson(a<<1|1);
	e[lson].lazy1+=e[a].lazy1;e[lson].ans+=e[lson].len*e[a].lazy1;
	e[rson].lazy1+=e[a].lazy1;e[rson].ans+=e[rson].len*e[a].lazy1;	
	e[a].lazy1=0;
	
}

void add_qu (int a, int l, int r, LL k ){
	if (e[a].l>=l && e[a].r<=r ){e[a].lazy1+=k; e[a].ans+=e[a].len*k; return;}
	if (e[a].lazy1)
		xia_fang(a);//lazy標記下放操作  詳見48行 
	int mid(e[a].l+e[a].r>>1),lson(a<<1),rson(a<<1|1);
	if (r<=mid)	add_qu(lson,l,r,k);
	else if (l>mid)	add_qu(rson,l,r,k);
	else add_qu(lson,l,r,k),add_qu(rson,l,r,k);
	e[a].ans=e[lson].ans+e[rson].ans;
	return ;
}

LL fnd_dian (int a,int pos){
	if (e[a].l==pos && e[a].r==pos)	{return e[a].ans;}
	if (e[a].lazy1)
		xia_fang(a);//下放操作  詳見48行 
	int mid(e[a].l+e[a].r>>1),lson(a<<1),rson(a<<1|1);
	if (pos<=mid)	return fnd_dian(lson,pos);
	else if (pos>mid)	return fnd_dian(rson,pos);
}

int main (){
	n=wread();
	make_tre(1,1,n);
	m=wread();
	while (m--){
		int opr=wread();
		if (opr==1){
			int x=wread(),y=wread();LL k=ll_wread();//區間[x,y] 每個數+k
			add_qu(1, x, y, k);
		}
		else {
			int pos=wread();//查詢第i個數的值 
			print(fnd_dian(1, pos));
		}
	}
	return 0;
}