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  1. #include <bits/stdc++.h>
  2. using namespace std;
  3.  
  4. long long a[(int)1e5 + 50];
  5. int n;
  6.  
  7. void buildPrefixSum() { // O(n)
  8.    for(int i = 1; i < n; i++) {
  9.        a[i] += a[i - 1];
  10.    }
  11.  
  12. }
  13.  
  14. int getSum(int i, int j) { // O(1)
  15.    int sum = a[j];
  16.    if(i > 0) sum -= a[i - 1];
  17.    return sum;
  18. }
  19.  
  20. int main()
  21. {
  22.     ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
  23.     int t,a,b;
  24.     cin >> n;
  25.     for(int i = 0; i < n; i++)
  26.     {
  27. 		cin >> a[i];
  28. 	}
  29.     buildPrefixSum();
  30.     cin >> t;
  31.     while(t--)
  32.     {
  33.         cin >> a >> b;
  34.         cout << getSum(a,b) << "\n";
  35.     }
  36. }
  37.  
  38.  
  39.  
  40.  
Compilation error #stdin compilation error #stdout 0s 4312KB
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stdin
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Standard input is empty
compilation info 
prog.cpp: In function ‘int main()’:
prog.cpp:27:13: error: invalid types ‘int[int]’ for array subscript
   cin >> a[i];
             ^
stdout
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Standard output is empty
https://ideone.com/RgIfSE
language:
C++ (gcc 8.3)
created:
5 years ago
visibility:
public

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