how to reinstall bootstrap inangular code example

Example 1: how to add bootstrap in angular

@import "~bootstrap/dist/css/bootstrap.css"

 "styles": [
              "./node_modules/bootstrap/dist/css/bootstrap.css",
              "src/styles.css"              
            ],

Example 2: bootstrap in angular.json file

{  "$schema": "./node_modules/@angular/cli/lib/config/schema.json",  "version": 1,   "newProjectRoot": "projects",  "projects": {    "angular-bootstrap-examples": {      "projectType": "application",      "schematics": {},      "root": "",      "sourceRoot": "src",      "prefix": "app",      "architect": {        "build": {          "builder": "@angular-devkit/build-angular:browser",          "options": {            "outputPath": "dist/angular-bootstrap-examples",            "index": "src/index.html",            "main": "src/main.ts",            "polyfills": "src/polyfills.ts",            "tsConfig": "tsconfig.app.json",            "aot": true,            "assets": [              "src/favicon.ico",              "src/assets"            ],            "styles": [              "./node_modules/bootstrap/dist/css/bootstrap.css",              "src/styles.css"                          ],            "scripts": [              "./node_modules/jquery/dist/jquery.js",              "./node_modules/bootstrap/dist/js/bootstrap.js"            ]          },