河南CCPC省赛 咕咕的计数题 II（打表找规律）

#include <iostream>
#include <vector>
#include <queue>
#include <algorithm>
#include <map>
#include <cmath>
#include <cstdio>
#include <string>
#include <cstring>
#include <set>
#include <stack>
#include <iomanip>
#include <unordered_map>
#define x first
#define y second
#define PB push_back
#define mst(x,a) memset(x,a,sizeof(x))
#define all(a) begin(a),end(a)
#define rep(x,l,u) for(ll x=l;x<u;x++)
#define rrep(x,l,u) for(ll x=l;x>=u;x--)
#define sz(x) x.size()
#define IOS ios::sync_with_stdio(false);cin.tie(0);
#define seteps(N) setprecision(N)
#define lson (ind<<1)
#define rson (ind<<1|1)
using namespace std;
typedef unsigned long long ull;
typedef pair<int,int> PII;
typedef pair<char,char> PCC;
typedef long long ll;
typedef pair<ll,ll> PLL;
typedef __int128 lll;
constexpr int N=505;
constexpr int M=1e6+10;
constexpr int INF=0x3f3f3f3f;
constexpr int mod=1e9+7;
ll l,r,a;
ll cal(ll n){
    if(!n) return 0;
    ll u,ans=0;
    u=n/a;
    if(u>=a){
        ans+=n-a*a+1;
        n=a*a-1;
    }
    u=n/a;
    if(n>=u*a+u-1){
        ans+=(1+u)*u/2;
    }else{
        u--;
        ans+=(1+u)*u/2;
        ans+=n-(u+1)*a+1;
    }
    return ans;
}
void solve(){
    scanf("%lld%lld%lld",&a,&l,&r);
    printf("%lld\n",cal(r)-cal(l-1));
}
signed main(){
    //IOS;
    //freopen("test.in", "r", stdin);
    //freopen("test.out", "w", stdout);
    int t;scanf("%d",&t);
    while(t--)
        solve();
    return 0;
}