累加累乘例题

#include "stdafx.h"
//计算1*2*3.....
int main(int argc, char* argv[])
{
int sum=1,i=1,flag;
printf("请输入累乘末项:");
scanf("%d",&flag);
while(i<=flag)
{sum=sum*i;
i=i+1;
}
printf("%d\n",sum);
return 0;
}
*/

/*
//计算12+22+32+...
#include "stdafx.h"

int main(int argc, char* argv[])
{
int sum=0,i=12,flag,count=1;
printf("请输入累加次数:");
scanf("%d",&flag);
while(count<=flag)
{sum=sum+i;
i=i+10;
count=count+1;
}
printf("%d\n",sum);
return 0;
}
*/

/*
//计算1+3+5+7...
#include "stdafx.h"

int main(int argc, char* argv[])
{
int sum=0,i=1,flag,count=1;
printf("请输入累加次数:");
scanf("%d",&flag);
while(count<=flag)
{sum=sum+i;
i=i+2;
count=count+1;
}
printf("%d\n",sum);
return 0;
}
*/

/*
//计算1+1/2+1/3...
#include "stdafx.h"

int main(int argc, char* argv[])
{
double sum=0.0,i=1.0;
int flag,count=1;
printf("请输入累加项数:");
scanf("%d",&flag);
while(count<=flag)
{sum=sum+i;
count=count+1;
i=1.0/count;
}
printf("%lf\n",sum);
return 0;
}
*/

/*
//计算1+1/2-1/3+1/4...
#include "stdafx.h"

int main(int argc, char* argv[])
{
double sum=1,i=0.5;
int flag,count=2,symbol=-1;
printf("请输入累加项数:");
scanf("%d",&flag);
while(count<=flag)
{
symbol=symbol*(-1);
i=1.0/count*symbol;
sum=sum+i;
count=count+1;
}
printf("%lf\n",sum);
return 0;
}
*/

//计算圆周率
#include "stdafx.h"
int main(int argc, char* argv[])
{
double sum=0.0,i;
int flag,count=0,symbol=1;
printf("请输入累加项数:");
scanf("%d",&flag);
while(count<=flag)
{count=count+1;
i=1.0/(2*count-1)*symbol;
symbol=symbol*(-1);
sum=sum+i;
}
sum=sum*4;
printf("%lf\n",sum);
return 0;
}

累加累乘例题

原文：https://www.cnblogs.com/dyf2019/p/14631696.html