题解 | #尼科彻斯定理#

#include <stdio.h>
#include <math.h>

int main() {
    int m = 0;
    double m_2 = 0.0;
    int ret = 0;
    while (scanf("%d", &m) != EOF) { // 注意 while 处理多个 case
        m_2 = pow(m, 2);
        ret = m_2 - m + 1;
        for (int i = 0; i < m; i++, ret += 2){
            if (ret % 2 != 0){
                printf("%d",ret);
            }else{
                ret++;
                printf("%d",ret);
            }
            if (i != m-1){
                printf("%c", '+');
            }
        }
        printf("\n");
    }
    return 0;
}