#include<iostream>
#include<string.h>
using namespace std;
int main(){
int m, n;
cin >> m >> n;
int matrix[200][200];
memset(matrix, -1, sizeof(matrix));
int a = 0, b = 0;
for ( a = 0; a < m; a++) {
for (b = 0; b < n; b++) {
cin >> matrix[a][b];
}
}
a = 0, b = 0;
int count = 0;//
while (count < m * n) {
//下
while (a < m && matrix[a][b] != -1) {
cout << matrix[a][b] << " ";
matrix[a][b] = -1;//标记已经选过的
a++;
count++;
}
b++;//如果不满足条件,跳出循环,转向
a--;//修正a
//右
while (b < n && matrix[a][b] != -1){
cout << matrix[a][b] << " ";
matrix[a][b] = -1;
b++;
count++;
}
a--;
b--;
while (a >= 0 && matrix[a][b] != -1) {
cout << matrix[a][b] << " ";
matrix[a][b] = -1;
a--;
count++;
}
b--;
a++;
while (b >= 0 && matrix[a][b] != -1) {
cout << matrix[a][b] << " ";
matrix[a][b] = -1;
b--;
count++;
}
a++;
b++;
}
return 0;
}
这个算法,我如果把它初始化为0,判断条件也改为0,然后就会报超时错误。有点想不通,难道初始化为-1比0更快?