include [HTML_REMOVED]
using namespace std;
const int N = 100010;
int a[N], s[N];
int main()
{
int m, n;
scanf(“%d%d”, &n, &m);
for (int i = 1; i <= n; i++) scanf(“%d”, &a[i]);
for (int i = 1; i <= n; i++) s[i] = s[i -1] + a[i]; //初始化前缀和
while (m --)
{
int l, r;
scanf("%d%d", &l ,&r);
printf("%d\n", s[r] - s[l -1]);
}
return 0;
}