题解 | #尼科彻斯定理#

#include <stdio.h>
#include <string.h>

int main(){

    int n;
    scanf("%d", &n);
    int squ = n * n;
    int sun;

    if(squ % 2 == 0){
        int first = squ - (n / 2) * 2 + 1;
        printf("%d", first);
        for(int i = 1; i < n; i++){
           sun = first + i * 2;
           printf("+%d", sun); 
        }
    }

    else {
        int first = squ - (n - 1);
        printf("%d", first);
        for(int j = 1; j < n; j++){
            sun = first + j * 2;
            printf("+%d", sun);
        }
    }

    return 0;
}