[Error] 'int ABC(int, int, int, int)' redeclared as different kind of symbol

源代码：

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstring>
#include<sstream>
#include<queue>
//#include<map>
#include<vector>
#include<math.h>
using namespace std;
//#define int long long
#define forr(i,a,b) for(int i=a;i<=b;i++)
#define repp(i,a,b) for(int i=a;i>=b;i--)
#define INF 1e9
#define ll long long
#define MAXN 200005
const int _x[]={0,1,0,-1,0},_y[]={0,0,1,0,-1};
#define mem(a,n) memset(a,n,sizeof(a));
#define chkmax(a,b) a=a>b?a:b;
#define chkmin(a,b) a=a<b?a:b;
#include<set>
#include<stack>
#define DE puts("check");
#include<windows.h>
#define KEY_DOWN(VK_NONAME) ((GetAsyncKeyState(VK_NONAME) & 0x8000) ? 1:0)
using namespace std;
#define KTIME 300
bool ifdown=-1;
int ABC(int p1x,int p1y,int p2x,int p2y){
  return sqrt(abs(p1x-p2x)*abs(p1x-p2x)+abs(p1y-p2y)*abs(p1y-p2y));
}
int main(){
  POINT pt1,pt2;
  while(1){
    if(KEY_DOWN('J')){
      if(ifdown==0){
        GetCursorPos(&pt1);
        ifdown=1;
      }
      if(ifdown==1){
        GetCursorPos(&pt2);
        ifdown=0;
        mouse_event(MOUSEEVENTF_LEFTDOWN,0,0,0,0);
        Sleep(KTIME*ABC((int)pt1.x,(int)pt1.y,(int)pt2.x,(int)pt2.y));
        mouse_event(MOUSEEVENTF_LEFTUP,0,0,0,0);
      }
      if(ifdown==-1){
        ifdown=1;
      }
    }
  }
}

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