프로그래밍 QnA

#include

int main()
{
int 원섭,세희,상근,숭,강수;//학생
int 원섭점수,세희점수,상근점수,숭점수,강수점수;
int 평균값;
int T=40;

printf("원섭이점수:");
scanf("%d", &원섭);

printf("세희점수:");
scanf("%d", &세희);

printf("상근이점수:");
scanf("%d", &상근);

printf("숭이점수:");
scanf("%d", &숭);

printf("강수점수:");
scanf("%d", &강수);

#include

int main(void)
{
int val1, val2;
int result=0;
std::cout<<"두 개의 숫자입력: ";
std::cin>>val1>>val2;

if (val1, val2)
{
for (int i = val1 + 1; i < val2; i++)
result += i;

else
{
for (int i = val2 + 1; i < val1: i++)
result += i;
}

std::cout << "두 수 사이의 정수 합: " << result << std::endl;
return 0;
}

visual studio 2019 쓰고요

오류가 두가지인데
the selection cannot be launched and there are no recent launches
이거 뜨는 경우랑
no docker connections exist use docker explorer view to open one
어쩔땐 이게 뜨는데

뭐가 문제일까요

22:37:24 **** Build of configuration Debug for project Hello ****
make all
Building file: ../main.c
Invoking: GCC C Compiler
gcc -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"main.d" -MT"main.o" -o "main.o" "../main.c"
Finished building: ../main.c

Building target: Hello
Invoking: GCC C Linker
gcc -o "Hello" ./main.o
/usr/lib/gcc/x86_64-linux-gnu/7/../../../x86_64-linux-gnu/Scrt1.o: In function `_start':
(.text+0x20): undefined reference to `main'
makefile:29: recipe for target 'Hello' failed