Submission #67747

#	Time	Username	Problem	Language	Result	Execution time	Memory
67747		yusufake	XOR Sum (info1cup17_xorsum)	C++98	100 / 100	1464 ms	33900 KiB

xorsum

#include<bits/stdc++.h>
using namespace std;

#define mp make_pair
#define pb push_back
#define st first
#define nd second

typedef long long ll;
typedef pair < int , int > pp;
typedef vector < int > vi;

const int mod = 1e9 + 7;
const int N   = 1e6 + 6;

pp one[N],zer[N],O[N],Z[N];

int T[N],A[N],o,z,zz,oo,n,i,j,l,x,ans;
ll t;
int main (){
    scanf("%d",&n);
    for(i=1;i<=n;i++){
        scanf("%d",&A[i]);
        if(A[i]&1) one[++o] = mp(0,i);
        else zer[++z] = mp(0,i);
    }
   
    for(j=0;j<31;j++){           
        
        t = 0;
        /*
        for(i=1;i<=n;i++){
            x = A[i];
            if(x & (1<<j)){
                t += o+1 - (int)(lower_bound(one+1 , one+o+1 , mp((1<<j)-T[i] , -1)) - one);
                t += (int)(lower_bound(zer+1 , zer+z+1 , mp((1<<j)-T[i] , -1)) - zer-1);
            }
            else{
                t += z+1 - (int)(lower_bound(zer+1 , zer+z+1 , mp((1<<j)-T[i] , -1)) - zer);
                t += (int)(lower_bound(one+1 , one+o+1 , mp((1<<j)-T[i] , -1)) - one-1);
            }
        }
*/
        for(l=1,i=o; i ;i--){
            for(; l<=z && (1<<j)-zer[l].st > one[i].st ; l++);
            t += l-1;
        }
        for(l=o,i=1; i<=o ;i++){
            for(; l && (1<<j)-one[l].st <= one[i].st ; l--);
            t += o-l;
        }
        for(l=z,i=1; i<=z ;i++){
            for(; l && (1<<j)-zer[l].st <= zer[i].st ; l--);
            t += z-l;
        }
        for(l=1,i=z; i ;i--){
            for(; l<=o && (1<<j)-one[l].st > zer[i].st ; l++);
            t += l-1;
        }
        
        
        
        for(i=1;i<=n;i++)
            if((A[i]+A[i]) & (1<<j))
                t++;
        
     //   if(t&1) assert(0);
        t >>= 1;
        if(t&1)
            ans += 1 << j;
        
        for(i=1;i<=n;i++)
            T[i] += A[i] & (1 << j);
        ////
           zz = oo = 0;
        
        for(i=1;i<=z;i++){
            l = zer[i].nd;
            if(A[l] & (1<<j+1))
                O[++oo] = mp(T[l],l);
            else
                Z[++zz] = mp(T[l],l);
        }
        for(i=1;i<=o;i++){
            l = one[i].nd;
            if(A[l] & (1<<j+1))
                O[++oo] = mp(T[l],l);
            else
                Z[++zz] = mp(T[l],l);
        }
        
        for(i=1;i<=oo;i++) one[i]=O[i];  o = oo;
        for(i=1;i<=zz;i++) zer[i]=Z[i];  z = zz;
    
    
    }
    
    printf("%d",ans);
    return 0;
}

Compilation message (stderr)

xorsum.cpp: In function 'int main()':
xorsum.cpp:79:28: warning: suggest parentheses around '+' inside '<<' [-Wparentheses]
             if(A[l] & (1<<j+1))
                           ~^~
xorsum.cpp:86:28: warning: suggest parentheses around '+' inside '<<' [-Wparentheses]
             if(A[l] & (1<<j+1))
                           ~^~
xorsum.cpp:92:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
         for(i=1;i<=oo;i++) one[i]=O[i];  o = oo;
         ^~~
xorsum.cpp:92:42: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
         for(i=1;i<=oo;i++) one[i]=O[i];  o = oo;
                                          ^
xorsum.cpp:93:9: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
         for(i=1;i<=zz;i++) zer[i]=Z[i];  z = zz;
         ^~~
xorsum.cpp:93:42: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
         for(i=1;i<=zz;i++) zer[i]=Z[i];  z = zz;
                                          ^
xorsum.cpp:21:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
     ~~~~~^~~~~~~~~
xorsum.cpp:23:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d",&A[i]);
         ~~~~~^~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 11 / 11
• Subtask 3: 21 / 21
• Subtask 4: 38 / 38
• Subtask 5: 23 / 23