简单的输出成绩等级，我无了

求指导，更找不到错误了
#define _CRT_SECURE_NO_WARNINGS 1
#include
main()
{ float score;
printf("请输入成绩：");
scanf("%.1f", &score);
if (score >= 90 && score <= 100)
printf("等级A\n");
else if (score >= 80 && score < 90)
printf("等级B\n");
else if (score >= 70 && score < 80)
printf("等级C\n");
else if (score >= 60 && score < 70)
printf("等级D\n");
else
printf("成绩不合格\n");

}

#include <stdio.h>

int main(){
    float score;
    scanf("%f",&score);
    if(score>=90&&score<=100) 
    printf("A");
    else if(score>=80&&score<90) 
    printf("B");
    else if(score>=70&&score<80) 
    printf("C");
     else if(score>=60&&score<70) 
    printf("D");
      else
    printf("不及格");
    return 0;
}