50120. Consecutive 1's
難度：2/5 Used Time: 7:201
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75#include <stdio.h>
#include <stdlib.h>
#define max(a,b) ((a)>(b)?(a):(b))
int n;
int arr[1024][1024] = {0};
int max_len = 0;
void row(){
for(int i = 0; i < n; i++){
int cnt = 0;
for(int j = 0; j < n; j++){
if(arr[i][j] == 1) cnt++;
else{
max_len = max(max_len, cnt);
cnt = 0;
}
}
max_len = max(max_len, cnt);
}
}
void col(){
for(int i = 0; i < n; i++){
int cnt = 0;
for(int j = 0; j < n; j++){
if(arr[j][i] == 1) cnt++;
else{
max_len = max(max_len, cnt);
cnt = 0;
}
}
max_len = max(max_len, cnt);
}
}
void diag(){
for(int i = n - 1; i >= 0; i--){
int x = 0, y = i;
int cnt = 0;
while(x < n && y < n){
if(arr[x][y] == 1) cnt++;
else{
max_len = max(max_len, cnt);
cnt = 0;
}
x++, y++;
}
max_len = max(max_len, cnt);
}
for(int i = 1; i < n; i++){
int x = i, y = 0;
int cnt = 0;
while(x < n && y < n){
if(arr[x][y] == 1) cnt++;
else{
max_len = max(max_len, cnt);
cnt = 0;
}
x++, y++;
}
max_len = max(max_len, cnt);
}
}
int main(){
scanf("%d", &n);
for(int i = 0; i < n; i++) for(int j = 0; j < n; j++) scanf("%d", &arr[i][j]);
row();
col();
diag();
printf("%d\n", max_len);
}