What should be the Gulp path?

Question

npm

After writing npm config set prefix /usr/local on the command line , nothing at all stopped working, one error is written for any command:
Error: EPERM: operation not permitted, mkdir 'C:\Program Files\Git\usr\local'
TypeError : Cannot read property 'get' of undefined
at errorHandler (C:\Program Files\nodejs\node_modules\npm\lib\utils\error-ha ndler.js:205:18)
at C:\Program Files\nodejs\node_modules\ npm\bin\npm-cli.js:78:20
at cb (C:\Program Files\nodejs\node_modules\npm\lib\npm.js:228:22)
at C:\Program Files\nodejs\node_modules\npm \lib\npm.js:266:24
at C:\Program Files\nodejs\node_modules\npm\lib\config\core.js:83:7
at Array.forEach()
at C:\Program Files\nodejs\node_modules\npm\lib\config\core.js :82:13
at f (C:\Program Files\nodejs\node_modules\npm\node_modules\once\once.js:25:25)
at afterExtras (C:\Program Files\nodejs\node_modules\npm\lib\config\ core.js: 173:20)
at C:\Program Files\nodejs\node_modules\npm\node_modules\mkdirp\index.js:35:29
C:\Program Files\nodejs\node_modules\npm\lib\utils\error-handler.js:205
if (npm .config.get('json')) {
^
TypeError: Cannot read property 'get' of undefined
at process.errorHandler (C:\Program Files\nodejs\node_modules\npm\lib\utils\ error-handler.js:205 :18)
at emitOne(events.js:116:13)
at process.emit(events.js:211:7)
at process._fatalException (bootstrap_node.js:391:26)
Error: EPERM: operation not permitted, mkdir 'C:\Program Files\Git\usr\local'
TypeError: Cannot read property 'get' of undefined
at errorHandler (C: \Program Files\nodejs\node_modules\npm\lib\utils\error-ha ndler.js:205:18)
at C:\Program Files\nodejs\node_modules\npm\bin\npm-cli.js:78:20
at cb (C:\Program Files\nodejs\node_modules\npm\lib\npm.js:228:22)
at C:\Program Files\nodejs\node_modules\npm\lib\npm.js:266:24
at C:\ Program Files\nodejs\node_modules\npm\lib\config\core.js:83:7
at Array.forEach()
at C:\Program Files\nodejs\node_modules\npm\lib\config\core.js:82:13
at f(C:\Program Files\nodejs\node_modules\npm\node_modules\once\once.js:25:25 )
at afterExtras (C:\Program Files\nodejs\node_modules\npm\lib\config\core.js: 173:20)
at Conf. (C:\Program Files\nodejs\node_modules\npm\lib\config\cor e.js:229:20)
C:\Program Files\nodejs\node_modules\npm\lib\utils\error-handler.js:205
if (npm.config.get('json')) {
^
TypeError: Cannot read property 'get' of undefined
at process .errorHandler (C:\Program Files\nodejs\node_modules\npm\lib\utils\ error-handler.js:205:18)
at emitOne (events.js:116:13)
at process.emit (events.js:211 :7)
at process._fatalException (bootstrap_node.js:391:26)
Please tell me how to solve the problem