[plain]
#include

int main()
{
int i;
int a;
int b;
int c;
int n;

printf("please enter a number:");
scanf("%d", &n);

a=b=1;

for(i=3; i<=n; i++)
{
c=a+b;
a=b;
b=c;
}

printf("The result is %d\n", c);

return 0;
}

#include

int main()
{
int i;
int a;
int b;
int c;
int n;

printf("please enter a number:");
scanf("%d", &n);

a=b=1;

for(i=3; i<=n; i++)
{
c=a+b;
a=b;
b=c;
}

printf("The result is %d\n", c);

return 0;
}