c++:
#include <iostream>
using namespace std;
int main(){
int suma = 0;
int n;
cin>>n;
for(int i = 1, i<=n, i++){
suma = suma + i;
}
cout<<suma;
return 0;
}
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pseudocod:
declare suma = 0
declare n
read n
for i is smaller or = to n:
increment i
add i to suma
display suma