临时抱佛脚

简单树状数组模板

N = 100010
tr = [0 for i in range(N)]
a = [0 for i in range(N)]

def lowbit(x):
    return -x&x

def add(x, c):
    while x < N:
        tr[x] += c
        x += lowbit(x)

def query(x):
    res = 0
    while x:
        res += tr[x]
        x -= lowbit(x)
    return res

n, m = map(int, input().split())
a[1:n+1] = list(map(int, input().split()))

for i in range(1, n+1):
    add(i, a[i])

for i in range(m):
    l, r = list(map(int, input().split()))
    print(query(r)-query(l-1))