1 #include <bits/stdc++.h>
2 #define _for(i,a,b) for(int i = (a);i < b;i ++)
3 #define _rep(i,a,b) for(int i = (a);i > b;i --)
4 #define INF 0x3f3f3f3f
5 typedef long long ll;
6 using namespace std;
7 inline ll read()
8 {
9 ll ans = 0;
10 char ch = getchar(), last = ' ';
11 while(!isdigit(ch)) last = ch, ch = getchar();
12 while(isdigit(ch)) ans = (ans << 1) + (ans << 3) + ch - '0', ch = getchar();
13 if(last == '-') ans = -ans;
14 return ans;
15 }
16 inline void write(ll x)
17 {
18 if(x < 0) x = -x, putchar('-');
19 if(x >= 10) write(x / 10);
20 putchar(x % 10 + '0');
21 }
22 const int maxn = 50;
23 class HP
24 {
25 public : int len,s[maxn]; HP() {(*this) = 0;};
26 HP(int inte) {(*this)=inte;}; HP(const char*str) {(*this)=str;};
27 friend ostream& operator << (ostream &cout,const HP &x);
28 HP operator = (int inte); HP operator = (const char*str);
29 HP operator * (const HP &b);HP operator + (const HP &b);
30 HP operator - (const HP &b);HP operator / (const HP &b);
31 HP operator % (const HP &b);int Compare(const HP &b);
32 bool operator < (const HP &b);
33 };
34
35 ostream& operator << (ostream &cout,const HP &x)
36 {for(int i = x.len;i >= 1;i --) cout<<x.s[i];return cout;}
37
38 HP HP::operator = (const char *str)
39 {
40 len = strlen(str);
41 for(int i = 1;i <= len;i ++) s[i] = str[len-i]-'0';
42 return (*this);
43 }
44
45 HP HP::operator = (int inte)
46 {
47 if(inte==0) {len = 1;s[1] = 0;return (*this);};
48 for(len = 0;inte > 0;) {s[++len] = inte%10;inte /= 10;};
49 return (*this);
50 }
51
52 HP HP::operator * (const HP&b)
53 {
54 int i,j;HP c;c.len = len+b.len;
55 for(i = 1;i <= c.len;i ++) c.s[i] = 0;
56 for(i = 1;i <=len;i ++) for(j = 1;j <=b.len;j ++) c.s[i+j-1]+=s[i]*b.s[j];
57 for(i = 1;i < c.len;i ++) {c.s[i+1]+=c.s[i]/10;c.s[i]%=10;}
58 while(c.s[i]) {c.s[i+1]=c.s[i]/10;c.s[i]%=10;i ++;}
59 while(i>1&&!c.s[i]) i--;c.len = i;
60 return c;
61 }
62
63 HP HP::operator+(const HP &b)
64 {
65 int i;HP c;c.s[1] = 0;
66 for(i = 1;i <=len || i<=b.len || c.s[i];i ++)
67 {
68 if(i<=len) c.s[i]+=s[i];
69 if(i<=b.len) c.s[i]+=b.s[i];
70 c.s[i+1]=c.s[i]/10;c.s[i]%=10;
71 }
72 c.len = i-1;if(c.len==0) c.len = 1;
73 return c;
74 }
75
76 HP HP::operator-(const HP&b)
77 {
78 int i, j;HP c;
79 for(i = 1,j = 0;i <= len;i ++)
80 {
81 c.s[i] = s[i]-j;if(i<=b.len) c.s[i]-=b.s[i];
82 if(c.s[i]<0){j = 1;c.s[i]+=10;}else j = 0;
83 }
84 c.len = len;while(c.len>1&&!c.s[c.len]) c.len--;
85 return c;
86 }
87
88 int HP::Compare(const HP &y)
89 {
90 if(len>y.len) return 1;
91 if(len<y.len) return -1;
92 int i = len;
93 while((i>1)&&(s[i]==y.s[i])) i--;
94 return s[i]-y.s[i];
95 }
96
97 bool HP::operator < (const HP &y)
98 {
99 if(this->Compare(y)>=0) return false;
100 return true;
101 }
102
103 HP HP::operator / (const HP&b)
104 {
105 int i,j;HP d(0),c;
106 for(i = len;i > 0;i --)
107 {
108 if(!(d.len==1 && d.s[1]==0))
109 {for(j = d.len;j > 0;j --) d.s[j+1]=d.s[j];++d.len;}
110 d.s[1] = s[i]; c.s[i] = 0;
111 while((j = d.Compare(b))>=0)
112 {d=d-b;c.s[i]++;if(j==0) break;}
113 }
114 c.len = len;while((c.len>1)&&(c.s[c.len]==0)) c.len--;
115 return c;
116 }
117
118 HP HP::operator%(const HP&b)
119 {
120 int i,j;HP d(0);
121 for(i = len;i > 0;i --)
122 {
123 if(!(d.len==1 && d.s[1]==0))
124 {for(j = d.len;j > 0;j --) d.s[j+1]=d.s[j];++d.len;}
125 d.s[1] = s[i];
126 while((j = d.Compare(b))>=0) {d = d-b;if(j==0)break;}
127 }
128 return d;
129 }
130
131
132 int n,m;
133 HP A[81][81];
134 HP f[81][81][81];
135 HP base[81];
136
137 void Base()
138 {
139 base[0] = 1,base[1] = 2;
140 _for(i,2,81)
141 base[i] = base[i-1]*2;
142 }
143 int main()
144 {
145 ios::sync_with_stdio(false);
146 Base();
147 n = read(), m = read();
148 _for(i,1,n+1)
149 _for(j,1,m+1)
150 A[i][j] = read();
151
152 _for(i,1,n+1)
153 _rep(len,m,0)
154 _for(l,1,m-len+2)
155 {
156 int r = l+len-1;
157 if(f[i][l-1][r]+A[i][l-1]*base[m-r+l-1]
158 < f[i][l][r+1]+A[i][r+1]*base[m-r+l-1])
159 f[i][l][r] = f[i][l][r+1]+A[i][r+1]*base[m-r+l-1];
160 else
161 f[i][l][r] = f[i][l-1][r]+A[i][l-1]*base[m-r+l-1];
162 }
163
164 HP ans;
165 ans = 0;
166 _for(i,1,n+1)
167 {
168 HP tmp;
169 tmp = 0;
170 _for(j,1,m+1)
171 if(tmp < f[i][j][j]+A[i][j]*base[m])
172 tmp = f[i][j][j]+A[i][j]*base[m];
173 ans = ans+tmp;
174 }
175 cout << ans << endl;
176 return 0;
177 }
