#include <string.h> #include <iostream> #include <algorithm> #include <vector> #include <queue> #include <set> #include <map> #include <string> #include <math.h> #include <stdlib.h> #include <time.h> using namespace std; #define INF 0x7fffffff int c[105]; int main() { #ifdef sxk freopen("in.txt","r",stdin); #endif int n, a, b, t; while(scanf("%d",&n)!=EOF) { c[0] = 0; scanf("%d", &c[1]); for(int i=2; i<=n⑴; i++){ scanf("%d", &t); c[i] = c[i⑴] + t; } scanf("%d%d", &a, &b); printf("%d ", c[b⑴] - c[a⑴]); } return 0; }