#include<bits/stdc++.h>
        #include<ext/pb_ds/assoc_container.hpp>
		#include <ext/pb_ds/tree_policy.hpp>

        using namespace std;
        using namespace __gnu_pbds;

        #define lint                     long long 
        #define setbits(x)              __builtin_popcountll(x)
        #define zrbits(x)               __builtin_ctzll(x)
        #define zlbits(x)               __builtin_clzll(x)
        #define parsbits(x)             __builtin_parityll(x)
        #define mem(a, b)               memset(a, (b), sizeof(a))
        #define MOD                     1000000007
        #define inf                     1e17 
        #define neginf                  -1e17 
        #define sp(x,y)                 fixed<<setprecision(x)<<y
        #define testcase(t)             lint t; cin>>t; while(t--)
        #define power(a,b)              (double)pow((double)a,(double)b)
        #define FOR(i,n)                for(lint i=0;i<n;i++)
        #define gcd(a,b)                __gcd(a,b)
        #define PI                      3.1415926535
        #define pb                      push_back
        #define ss                      second
        #define ff                      first
        #define umap                    unordered_map           
        #define ummap                   unordered_multimap
        #define uset                    unordered_set
        #define umset                   unordered_multiset

         
        typedef unsigned long long   ull;

        typedef tree<int,null_type,less<int>,rb_tree_tag,
        tree_order_statistics_node_update> indexed_set;
         
        void c_p_c()
        {
            ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
       // #ifndef ONLINE_JUDGE
          //  freopen("input1.txt", "r", stdin);
         //   freopen("output1.txt", "w", stdout);
       // #endif
        }

        lint me(lint x, lint y, lint p)  
        {  
            lint res = 1;     
      
            x = x % p; 
       
            if (x == 0) return 0; 
      
            while (y > 0)  
            {  
            
                if (y & 1)  
                res = (res*x) % p;  
      
              
                y = y>>1;  
                x = (x*x) % p;  
            }  
            return res;  
        }

        struct hash_pair { 
    	template <class T1, class T2> 
    	size_t operator()(const pair<T1, T2>& p) const
    		{ 
       			 auto hash1 = hash<T1>{}(p.first); 
       			 auto hash2 = hash<T2>{}(p.second); 
       			 return hash1 ^ hash2; 
    		} 
		};


/*---------------------------SOLUTION---------------------------------*/
     

        void solve()
        {
            ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
            lint n;
            cin>>n;
            lint x=(lint)ceil((double)n/(double)1000);
            x=1000*x-n;
            cout<<x<<endl;


        }


        int main()
        {
            c_p_c();
            lint flg99=0;
            if(flg99==1)
            {
                testcase(t)
                {
                    solve();
                }
            }
            else
            {
                solve();
            }
            return 0;
        
        }
            
        
            

            

            



Measured memory_bytes: 3764