import sys, re
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians, log2
from itertools import accumulate, permutations, combinations, product
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from bisect import bisect, bisect_left
from fractions import gcd
from heapq import heappush, heappop
from functools import reduce

def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def LIST(): return list(map(int, input().split()))
def ZIP(n): return zip(*(MAP() for _ in range(n)))
sys.setrecursionlimit(10 ** 9)
mod = 10 ** 9 + 7
INF = float('inf')

class Lazysegtree:
    #RAQ
    def __init__(self, A, intv, initialize=True, segf=min):
        #区間は 1-indexed で管理
        self.N = len(A)
        self.N0 = 2**(self.N-1).bit_length()
        self.intv = intv
        self.segf = segf
        self.lazy = [0]*(2*self.N0)
        if initialize:
            self.data = [intv]*self.N0 + A + [intv]*(self.N0 - self.N)
            for i in range(self.N0-1, 0, -1):
                self.data[i] = self.segf(self.data[2*i], self.data[2*i+1]) 
        else:
            self.data = [intv]*(2*self.N0)

    def _ascend(self, k):
        k = k >> 1
        c = k.bit_length()
        for j in range(c):
            idx = k >> j
            self.data[idx] = self.segf(self.data[2*idx], self.data[2*idx+1]) \
            + self.lazy[idx]
            
    def _descend(self, k):
        k = k >> 1
        idx = 1
        c = k.bit_length()
        for j in range(1, c+1):
            idx = k >> (c - j)
            ax = self.lazy[idx]
            if not ax:
                continue
            self.lazy[idx] = 0
            self.data[2*idx] += ax
            self.data[2*idx+1] += ax
            self.lazy[2*idx] += ax
            self.lazy[2*idx+1] += ax
    
    def query(self, l, r):
        L = l+self.N0
        R = r+self.N0
        Li = L//(L & -L)
        Ri = R//(R & -R)
        self._descend(Li)
        self._descend(Ri - 1)
        
        s = self.intv                                                              
        while L < R:
            if R & 1:
                R -= 1
                s = self.segf(s, self.data[R])
            if L & 1:
                s = self.segf(s, self.data[L])
                L += 1
            L >>= 1
            R >>= 1
        return s
    
    def update(self, l, r, x):
        L = l+self.N0
        R = r+self.N0

        Li = L//(L & -L)
        Ri = R//(R & -R)
        
        while L < R :
            if R & 1:
                R -= 1
                self.data[R] += x
                self.lazy[R] += x
            if L & 1:
                self.data[L] += x
                self.lazy[L] += x
                L += 1
            L >>= 1
            R >>= 1
        
        self._ascend(Li)
        self._ascend(Ri-1)

n, q = MAP()
lazyseg = Lazysegtree([0]*n, INF)
for _ in range(q):
    query = input().split()
    if query[0] == "0":  # add
        _, s, t, x = query
        s, t, x = map(int, [s, t, x])
        lazyseg.update(s, t+1, x)

    else:  # find
        _, s, t = query
        s, t = map(int, [s, t])
        print(lazyseg.query(s, t+1))



Measured memory_bytes: 21316