#include "stdio.h"
#include "ctype.h"
 
int main()
{
    int hour,minutes;
    char time[2];
 
    printf("Enter a 12-hour time:");
    scanf("%d:%d%s",&hour,&minutes,time);
 
    if(toupper(time[0])=='P' && toupper(time[1])=='M')
    {
        hour+=12;
    }
    printf("%d:%d",hour,minutes);
}为什么最后输出的minutes的值为0？
把%s删掉了就没有这个情况

scanf("%d:%d%s",&hour,&minutes,time)去掉冒号，改为scanf("%d%d%s",&hour,&minutes,time)