//

//  main.c

//  53 - 数列求和 - 李洪强

//

//  Created by vic fan on 16/10/15.

//  Copyright © 2016年 李洪强. All rights reserved.

//

#include <stdio.h>

int main(int argc, const char * argv[]) {

//1 ,3,5,7...

//中间有多少项相加

//sum = 0 + 1;

//sum = 1 + 3;

//sum = 4 + 5;

//sum += 2 *i + 1;

int i = 0;

int sum = 0;

while (i < 49) {

sum += 2 *i + 1;

i++;

}

printf("%d\n",sum);

//*******************

//和

int sum = 0;

//公差

int gongCha = 1;

//首项

int shouXiang = 1;

int i = 0;

while (i < 100) {

sum += gongCha *i +shouXiang;

i++;

}

printf("%d\n",sum);

return 0;

}