编辑代码

#include <stdio.h>  
  
int stairMethods(int stairCount)  
{  
    if(stairCount<1) {  
        return 0;  
    }  
  
    if(stairCount==1) {  
        return 1;  
    }  
  
    if(stairCount==2) {  
        return 2;  
    }  
  
    int prev1 = 1;  
    int prev2 = 2;  
    int current = 0;  
    for(int i = 3; i <= stairCount; i++) {  
        current = prev1 + prev2;  
        prev1 = prev2;  
        prev2 = current;  
    }  
    return current;  
}  
  
int main () {  
    
    printf("%d\n",stairMethods(0));  
    printf("%d\n",stairMethods(1));  
    printf("%d\n",stairMethods(2));  
    printf("%d\n",stairMethods(4));  
    printf("%d\n",stairMethods(10));  
    return 0;  
}