long long getsum(long long *arr,long long pos){long long sum=0;while(pos) sum+=arr[pos],pos-=lowbit(pos);return sum;
}
long long query(long long x,long long y){return y*getsum(d1,y)-(x-1)*getsum(d1,x-1)-(getsum(d2,y)-getsum(d2,x-1));
}

void add(long long *arr,long long pos,long long x){while(pos<=n) arr[pos]+=x,pos+=lowbit(pos);
}

void change(long long l,long long r,long long x){add(d1,l,x);add(d1,r+1,-x);add(d2,l,x*(l-1));add(d2,r+1,-x*r);
}

#include<cstdio>
#include<algorithm>
//long long tree[100001];
long long n,m;
long long d1[100001];
long long d2[100001];
inline long long lowbit(long long x)
{return x&-x;
}
/*void add(long long x,long long k)//μ￥μ?DT??
{while(x<=n){tree[x]+=k;x+=lowbit(x);}
}
long long sum(long long pos)
{//????2é?ˉ long long sum=0;while(pos){sum+=tree[pos];pos-=lowbit(pos);return sum;}
}
void add_ex(long long pos,long long x)
{//????DT?? while(pos<=n){detla[pos]+=x;pos+=lowbit(pos);}
}
void sum_ex(long long l,long long r,long long x)
{add_ex(l,x);add(r+1,-x);
}
long long sum_ex(long long pos)//μ￥μ?2é?ˉ
{long long sum=0;while(pos){sum+=detla[pos];pos-=lowbit(pos);}return sum;
}*/
//ò???ê?????DT??+????2é?ˉ
void add(long long *arr,long long pos,long long x){while(pos<=n) arr[pos]+=x,pos+=lowbit(pos);
}
void change(long long l,long long r,long long x){add(d1,l,x);add(d1,r+1,-x);add(d2,l,x*(l-1));add(d2,r+1,-x*r);
}
long long getsum(long long *arr,long long pos){long long sum=0;while(pos) sum+=arr[pos],pos-=lowbit(pos);return sum;
}
long long query(long long x,long long y){return y*getsum(d1,y)-(x-1)*getsum(d1,x-1)-(getsum(d2,y)-getsum(d2,x-1));
}//ò???ê?×??μ
/*
void build(long long n){for(long long i=1;i<=n;i++){tree[i]=a[i];long long t=lowbit(i);for(long long j=1;j<t;j*=2)tree[i]=std::max(tree[i],tree[i-j]);}
}
void add(long long pos,long long x){a[pos]=x;while(pos<=n){tree[pos]=a[pos];long long t=lowbit(i);for(long long j=1;j<t;j++){tree[i]=std::max(tree[i],tree[i-j]);}pos+=lowbit(pos);}
}
long long query(long long l,long long r){long long ans=a[r];while(1){ans=std::max(ans,tree[r]);if(r==l)break;r--;while(r-l>=lowbit(r))ans=std::max(ans,tree[r]),r-=lowbit(r);}return ans;
}
*/
int main()//ê÷×′êy×é′ó?￡°?
{scanf("%lld%lld",&n,&m);long long a,b=0;for(long long i=1;i<=n;i++){scanf("%lld",&a);b=a-b;add(d1,i,b);add(d2,i,(i-1)*b);b=a;}while(m--){long long op;scanf("%lld",&op);if(op==1){//???μ long long x,y,z;scanf("%lld%lld%lld",&x,&y,&z);change(x,y,z);}else{long long x,y;//2é?ˉ scanf("%lld%lld",&x,&y);printf("%lld\n",query(x,y));}}
}