C++ Build and Run Externally

{
    "cmd": ["start", "cmd", "/c",  "echo Compiling... && g++ '${file}' -o ${file_base_name} && cls && ${file_base_name} && echo. && pause"],
    "file_regex": "^(..[^:]*):([0-9]+):?([0-9]+)?:? (.*)$",
    "working_dir": "${file_path}",
    "selector": "source.c, source.cpp",
    "shell": true,

    "variants":
    [
        {
            "name": "Build",
            "cmd": ["g++", "${file}", "-o", "${file_base_name}"],
            "shell": true
        },
        {
            "name": "Run",
            "cmd" : ["start", "cmd", "/c", "${file_base_name} && echo. && pause"],
            "shell": true
        },
        {
            "name": "Run with input.txt",
            "cmd" : ["start", "cmd", "/c", "${file_base_name} < input.txt && echo. && pause"],
            "shell": true
        }
    ]
}