BZOJ 1127
1 2 #include <cstdio> 3 #include <cstring> 4 #include <iostream> 5 #include <algorithm> 6 #define M 2020 7 using namespace std; 8 int n,k,a[M][M]; 9 long long sum[M][M]; 10 long long Get_Sum(int x1,int y1,int x2,int y2) 11 { 12 return sum[x2][y2]-sum[x1-1][y2]-sum[x2][y1-1]+sum[x1-1][y1-1]; 13 } 14 void Output(int x1,int y1,int x2,int y2) 15 { 16 while( Get_Sum(x1,y1,x2,y2)>k*2 ) 17 { 18 if(x1==x2) 19 y2--; 20 else 21 { 22 if( Get_Sum(x1+1,y1,x2,y2)>=k ) 23 x1++; 24 else 25 x2--; 26 } 27 } 28 printf("%d %d %d %d\n",y1,x1,y2,x2); 29 exit(0); 30 } 31 void Monotonous_Stack(int base,int h[]) 32 { 33 static int stack[M],top; 34 static int l[M],r[M]; 35 int i; 36 37 for(top=0,i=1;i<=n+1;i++) 38 { 39 while( top && h[stack[top]]>h[i] ) 40 r[stack[top--]]=i-1; 41 stack[++top]=i; 42 } 43 for(top=0,i=n;i>=0;i--) 44 { 45 while( top && h[stack[top]]>h[i] ) 46 l[stack[top--]]=i+1; 47 stack[++top]=i; 48 } 49 for(i=1;i<=n;i++) 50 if(h[i]) 51 { 52 long long temp=Get_Sum(base-h[i]+1,l[i],base,r[i]); 53 if( temp>=k ) 54 Output(base-h[i]+1,l[i],base,r[i]); 55 } 56 } 57 int main() 58 { 59 int i,j; 60 cin>>k>>n; 61 for(i=1;i<=n;i++) 62 for(j=1;j<=n;j++) 63 { 64 scanf("%d",&a[i][j]); 65 if( a[i][j]>=k && a[i][j]<=k*2 ) 66 { 67 printf("%d %d %d %d\n",j,i,j,i); 68 return 0; 69 } 70 sum[i][j]=sum[i-1][j]+sum[i][j-1]-sum[i-1][j-1]+a[i][j]; 71 } 72 static int h[M]; 73 for(i=1;i<=n;i++) 74 { 75 for(j=1;j<=n;j++) 76 h[j]=a[i][j]>k*2?0:h[j]+1; 77 Monotonous_Stack(i,h); 78 } 79 puts("NIE"); 80 return 0; 81 }
