#include <stdio.h>
int main() {
char ch;
scanf("%c", &ch);
if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z')) {
printf("\n");
} else if (ch >= '0' && ch <= '9') {
printf("\n");
} else {
printf("\n");
}
return 0;
}

#include <stdio.h>
int main() {
int a, b, c;
scanf("%d %d %d", &a, &b, &c);
if (a < b) {
int t = a;
a = b;
b = t;
}
if (a < c) {
int t = a;
a = c;
c = t;
}
if (b < c) {
int t = b;
b = c;
c = t;
}
printf("%d,%d,%d\n", a, b, c);
return 0;
}

#include <iostream>
#include <cctype>
using namespace std;
int main() {
char ch;
cin >> ch;
if (isalpha(ch)) {
cout << "字母" << endl;
} else if (isdigit(ch)) {
cout << "数字" << endl;
} else {
cout << "其他字符" << endl;
}
return 0;
}

#include <iostream>
#include <cctype>
using namespace std;
int main() {
char ch;
cin >> ch;
if (isalpha(ch)) {
cout << "字母" << endl;
} else if (isdigit(ch)) {
cout << "数字" << endl;
} else {
cout << "其他字符" << endl;
}
return 0;
}

#include <stdio.h>
int main() {
int num1, num2, num3;
scanf("%d %d %d", &num1, &num2, &num3);
if (num1 < num2) {
int temp = num1;
num1 = num2;
num2 = temp;
}
if (num1 < num3) {
int temp = num1;
num1 = num3;
num3 = temp;
}
if (num2 < num3) {
int temp = num2;
num2 = num3;
num3 = temp;
}
printf("%d,%d,%d\n", num1, num2, num3);
return 0;
}

#include <stdio.h>
int main() {
float s;
scanf("%f", &s);
if(s<0||s>100) printf("成绩超出了范围\n");
else if(s<60) printf("不及格\n");
else if(s<70) printf("中等\n");
else if(s<85) printf("良好\n");
else printf("优秀\n");
return 0;
}

#include <stdio.h>
int main() {
int a, b;
char op;
scanf("%d%c%d", &a, &op, &b);
if(op == '+') printf("%d\n", a + b);
else if(op == '-') printf("%d\n", a - b);
else if(op == '*') printf("%d\n", a * b);
else if(op == '/') {
if(b != 0) printf("%d\n", a / b);
else printf("Division by zero error!\n");
}
else printf("Invalid operator!\n");
return 0;
}

#include <stdio.h>
int main() {
float x, y;
scanf("%f %f", &x, &y);
float d = (x - 1)*(x - 1)+(y - 1)*(y - 1);
if(d < 1) printf("单位圆内\n");
else if(d == 1) printf("单位圆上\n");
else printf("单位圆外\n");
return 0;
}

#include <stdio.h>
#include <math.h>
int main() {
int x;
double result;
scanf("%d", &x);
if(x>20) result = 1.0/x + fabs(x);
else if(x>=10 && x<=20) result = sqrt(3*x)-2;
else result = x*x + 3*x + 2;
printf("%.2f\n", result);
return 0;
}