洛谷p2615,问一下为什么我的代码出来的结果不对
//P2615 [NOIP2015 提高组] 神奇的幻方
#include
using namespace std;
int a[40][40] = {};
int main() {
int n=0;
cin >> n;
a[0][n / 2] = 1;
int x = 0, y = n / 2;
for (int i = 2; i < n * n; i++) {
if (x == 0 && y != n-1){
a[n][y + 1] = i;
x = n-1;
y ++;
}
else if (x != 0 && y == n-1){
a[x - 1][0] = i;
x --;
y = 0;
}
else if (x == 0 && y == n-1){
a[x + 1][y] = i;
x ++;
}
else if (x != 0 && y != n){
if (a[x - 1][y + 1] = 0&&x-1>=1&&y+1<=n){
a[x - 1][y + 1] = i;
x --;
y ++;
}
else{
a[x + 1][y] = i;
x ++;
}
}
}
for (int i = 1; i <= n; i++) {
for (int j = 1; j <= n; j++) {
cout << a[i][j] << " ";
}
cout << endl;
}
return 0;
}
该回答引用chatgpt:
你的代码中存在一个错误。在第四个条件语句中,你使用了单个等于号(=)而不是双等于号(==)。这会将判断变成赋值,导致程序逻辑错误。将它改为双等于号就可以了。修改后的代码如下:
//P2615 [NOIP2015 提高组] 神奇的幻方
#include<iostream>
using namespace std;
int a[40][40] = {};
int main() {
int n=0;
cin >> n;
a[0][n / 2] = 1;
int x = 0, y = n / 2;
for (int i = 2; i < n * n; i++) {
if (x == 0 && y != n-1){
a[n][y + 1] = i;
x = n-1;
y ++;
}
else if (x != 0 && y == n-1){
a[x - 1][0] = i;
x --;
y = 0;
}
else if (x == 0 && y == n-1){
a[x + 1][y] = i;
x ++;
}
else if (x != 0 && y != n){
if (a[x - 1][y + 1] == 0&&x-1>=1&&y+1<=n){
a[x - 1][y + 1] = i;
x --;
y ++;
}
else{
a[x + 1][y] = i;
x ++;
}
}
}
for (int i = 1; i <= n; i++) {
for (int j = 1; j <= n; j++) {
cout << a[i][j] << " ";
}
cout << endl;
}
return 0;
}
不知道你这个问题是否已经解决, 如果还没有解决的话:题目链接:
P1525 [NOIP2010 提高组] 关押罪犯 - 洛谷 | 计算机科学教育新生态 (luogu.com.cn)#include <iostream>
#include <algorithm>
using namespace std;
struct Person {
int x;
int y;
int z;
} f[100010];
int fa[20005], b[20005];
bool Com(Person p1, Person p2) {
return p1.z > p2.z;
}
int find(int x) {
if (fa[x] == x) {
return x;
} else {
fa[x] = find(fa[x]);
return fa[x];
}
}
void merge(int x, int y) {
int xx = find(x);
int yy = find(y);
fa[xx] = yy;
}
bool check(int x, int y) {
if (find(x) == find(y)) {
return true;
} else {
return false;
}
}
int main() {
int n, m;
cin >> n >> m;
for (int i = 1; i <= n; i++) {
fa[i] = i;
}
for (int i = 1; i <= m; i++) {
cin >> f[i].x >> f[i].y >> f[i].z;
}
sort(f + 1, f + m + 1, Com);
for (int i = 1; i <= m; i++) {
if (check(f[i].x, f[i].y)) {
cout << f[i].z;
return 0;
} else {
if (!b[f[i].x]) {
b[f[i].x] = f[i].y;
} else {
merge(b[f[i].x], f[i].y);
}
if (!b[f[i].y]) {
b[f[i].y] = f[i].x;
} else {
merge(b[f[i].y], f[i].x);
}
}
}
cout << 0;
return 0;
}