Calculate the factorial sum from 1 to 20 and write it into a program

# include

int main()

double a,i=1,b=1,sum=0;

for(a=1;a<=3;a++)

This curly brace is not necessary.

for(i=1;i<=a;i++)

b=b*i;Write programs with indentation (formatting).

That's not necessary.

sum=sum+b;

Here you need to add:

b=1;printf("sum=%e",sum);

return 0;

For assembly language, the results are sufficiently expressed in two words.

option arithmetic decimal_highlet fact=1

let sum=0

for i=1 to 20

let fact=fact*i

let sum=sum+fact

print i,fact,sum

next iend

It's good to be together? There is no point in the house. You want me to go to ** to have fun, you want me to go ** to have fun. You want.

Personal testing is available. long jiecheng(int x)long int i,k=1;

for(i=1;i<=x;i++)

k=k*i;

return k;

int main()

long int j,k=0;

int i;

for(i=1;i<=20;i++)

j=jiecheng(i);

k+=j;printf("%ld",k);

The result of the output is 2561327494111820313<>

Classic examples of the C language are 1+2!+3!+.20!of and.

1. Program analysis: This program just turns accumulation into accumulation.

2. Program source**.

main()

float n,s=0,t=1;

for(n=1;n<=20;n++)

t*=n;s+=t;

printf("1+2!+3!..20!=%e",s);

3. Introduction to C language:

1) C language is a general-purpose computer programming language with a wide range of applications. C is designed to provide a programming language that can compile in a simple way, handle low-level memory, generate a small amount of machine code, and run without any runtime support.

2) Although C provides many low-level processing functions, it still maintains good cross-platform characteristics, and C language programs written in a standard specification can be compiled on many computer platforms, including some embedded processors (microcontrollers or MCUs) and supercomputers and other operating platforms.

3) In the eighties of the twentieth century, in order to avoid the differences in the C language grammar used by various developers, the National Bureau of Standards of the United States formulated a complete set of international standard grammar for the C language, called ANSI C, as the initial standard for the C language.

It's just a slight change to the above brother.

#include

void main()

printf("%d", s);

Kun、It means that the second one is better.。。。 Tan Haoqiang killed people and didn't pay for his life...

<>2. Set a temporary variable in the program and the sum variable that accepts the sum of the factorials, first iterate the numbers within 20 in the loop, and then calculate the factorial of each number, and add them up, because it is a very large number of quiet files, so the sum here is of the double type, and finally the result can be output:

3. Finally, debug the compiler, and you will see the sum of the output within the 20th factor, which is a very large number. The above is how to find the factorial sum within 20 in C