1023: 大小写转换

# include <stdio.h>
# include <math.h>

int main(){
    char ch;

    scanf("%c", &ch);
    if (ch >= 'a' && ch <= 'z')
        ch = ch - 32;//小写转大写，a是97 A是65
    printf("%c\n", ch);
    

    return 0;
}